Ancient-Philosophy_-A-New-History-of-Western-Philosophy-Volume-1-_New-History-of-Western-Philosophy_333
                     Ancient Philosophy
This is the remarkable story of the birth of philosophy, its 
flourishing in the ancient Mediterranean world, and the 
development of ideas which have shaped the course of Western 
thought and society.
Sir Anthony Kenny’s stimulating account begins with 
Pythagoras and Thales, and ends with St Augustine, who 
handed on the torch of philosophy to the Christian age. At the 
centre of the narrative are the two great figures of Plato and 
Aristotle, who between them set the agenda for philosophy for 
the next two millenia, and whose influence is as profound today 
as ever.
The fruit of a lifetime’s scholarship and insight, Ancient 
Philosophy sets the philosophers and their ideas in historical 
context, and explains the significance and impact of each wave 
of new ideas. It is the first volume in a magisterial new series, 
which brings the history of philosophy alive to anyone who 
wants to understand the roots of Western civilization.
Sir Anthony Kenny has been President of the British 
Academy, and Pro-Vice-Chancellor of the University of Oxford. 
He has written many acclaimed books on the philosophy of 
mind, the philosophy of religion, and the history of philosophy, 
including both scholarly and popular works on Aristotle, 
Aquinas, Descartes, and Wittgenstein.
A New History of Western Philosophy
Anthony Kenny
Volume 1: Ancient Philosophy    Volume 3: The Rise of Modern 
Philosophy
Volume 2: Medieval Philosophy    Volume 4: Philosophy in the Modern 
World
A NEW HISTORY OF WESTERN PHILOSOPHY
VOLUME 1
Ancient Philosophy
ANTHONY
KENNY
CLARENDON PRESS • OXFORD
OXFORD
UNIVERSITY PRESS
Great Clarendon Street, Oxford ox2 6dp Oxford University Press is a 
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Published in the United States by Oxford University Press Inc., New 
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© Sir Anthony Kenny 2004 The moral rights of the author have 
been asserted Database right Oxford University Press (maker)
First published 2004 First published in paperback 2006
All rights reserved. No part of this publication may be reproduced, 
stored in a retrieval system, or transmitted, in any form or by any 
means, without the prior permission in writing of Oxford University 
Press, or as expressly permitted by law, or under terms agreed 
with the appropriate reprographics rights organization. Enquiries 
concerning reproduction outside the scope of the above should be 
sent to the Rights Department, Oxford University Press, at the 
address above
You must not circulate this book in any other binding or cover and 
you must impose this same condition on any acquirer
British Library Cataloguing in Publication Data Data available
Library of Congress Cataloging in Publication Data Data available
Typeset by SPI Publisher Services, Pondicherry, India Printed in 
Great Britain on acid-free paper by Biddles Ltd., King’s Lynn ISBN 
0-19-875273-3 978-0-19-875273-8 ISBN 0-19-875272-5 (Pbk.) 978-
0-19-875272-1 (Pbk.)
13579 10 8642
SUMMARY OF CONTENTS
List of Contents 
   vii
Map x 
Introduction xi
1.    Beginnings: From Pythagoras to Plato 1
2.    Schools of Thought: From Aristotle to Augustine 65
3.    How to Argue: Logic 116
4.    Knowledge and its Limits: Epistemology 145
5.    How Things Happen: Physics 178
6.    What There Is: Metaphysics 199
7.    Soul and Mind 229
8.    How to Live: Ethics 257
9.    God 289
Chronology 317
List of Abbreviations and Conventions 319 Bibliography 
323 List of Illustrations 331 Index 335
CONTENTS
Map x Introduction xi
1.    Beginnings: From Pythagoras to Plato 1
The Four Causes 1 The Milesians 4 The Pythagoreans 9 
Xenophanes 11 Heraclitus 12
Parmenides and the Eleatics 17
Empedocles 20
Anaxagoras 24
The Atomists 26
The Sophists 28
Socrates 32
The Socrates of Xenophon 35 The Socrates of Plato 37 
Socrates’ Own Philosophy 41 From Socrates to Plato 45 
The Theory of Ideas 49 Plato’s Republic 56 The Laws 
and the Timaeus 60
2.    Schools of Thought: From Aristotle to Augustine 65
Aristotle in the Academy 65 Aristotle the Biologist 69 
The Lyceum and its Curriculum 73 Aristotle on Rhetoric 
and Poetry 75 Aristotle’s Ethical Treatises 79 Aristotle s 
Political Theory 82 Aristotle s Cosmology 87 The Legacy 
of Aristotle and Plato 89 Aristotle s School 91 Epicurus 
94
CONTENTS
Stoicism 96
Scepticism in the Academy 100 Lucretius 
101 Cicero 103
Judaism and Christianity 104
The Imperial Stoa 106
Early Christian Philosophy 109
The Revival of Platonism and 
Aristotelianism 111
Plotinus and Augustine 112
3.    How to Argue: Logic 116
Aristotle’s Syllogistic 117 The de 
Interpretations and the Categories 123 
Aristotle on Time and Modality 129 Stoic 
Logic 136
4.    Knowledge and its Limits: 
Epistemology 145
Presocratic Epistemology 145
Socrates, Knowledge, and Ignorance 148
Knowledge in the Theaetetus 152
Knowledge and Ideas 156
Aristotle on Science and Illusion 161
Epicurean Epistemology 166
Stoic Epistemology 169
Academic Scepticism 173
Pyrrhonian Scepticism 175
5.    How Things Happen: Physics 178
The Continuum 178
Aristotle on Place 182
Aristotle on Motion 184
Aristotle on Time 186
Aristotle on Causation and Change 189
The Stoics on Causality 192
Causation and Determinism 194
Determinism and Freedom 196
6.    What There Is: Metaphysics 199
Parmenides' Ontology 200
viii
CONTENTS
Plato’s Ideas and their Troubles 205 
Aristotelian Forms 216 Essence and 
Quiddity 218 Being and Existence 223
7.    Soul and Mind 229
Pythagoras’ Metempsychosis 229 
Perception and Thought 232 
Immortality in Plato’s Phaedo 234 The 
Anatomy of the Soul 237 Plato on 
Sense-Perception 240 Aristotle’s 
Philosophical Psychology 241 
Hellenistic Philosophy of Mind 248 
Will, Mind, and Soul in Late Antiquity 
251
8.    How to Live: Ethics 257
Democritus the Moralist 257
Socrates on Virtue 260
Plato on Justice and Pleasure 264
Aristotle on Eudaimoma 266
Aristotle on Moral and Intellectual 
Virtue 269
Pleasure and Happiness 274
The Hedonism of Epicurus 277
Stoic Ethics 280
9.    God 289
Xenophanes’ Natural Theology 289 
Socrates and Plato on Piety 290 
Plato’s Evolving Theology 293 
Aristotle’s Unmoved Movers 296 The 
Gods of Epicurus and the Stoics 302 
On Divination and Astrology 308 The 
Trinity of Plotinus 311
Chronology 317
List of Abbreviations and Conventions 
319 Bibliography 323 List of 
Illustrations 331 Index 335
ix

INTRODUCTION
Why should one study the history of philosophy? There are 
many reasons, but they fall into two groups: philosophical and 
historical. We may study the great dead philosophers in order to 
seek illumination upon themes of present-day philosophical 
inquiry. Or we may wish to understand the people and societies 
of the past, and read their philosophy to grasp the conceptual 
climate in which they thought and acted. We may read the 
philosophers of other ages to help to resolve philosophical 
problems of abiding concern, or to enter more fully into the 
intellectual world of a bygone era.
In this history of philosophy, from the beginnings to the present 
day, I hope to further both purposes, but in different ways in 
different parts of the work, as I shall try to make clear in this 
Introduction. But before outlining a strategy for writing the 
history of philosophy, one must pause to reflect on the nature of 
philosophy itself. The word ‘philosophy’ means different things in 
different mouths, and correspondingly ‘the history of philosophy’ 
can be interpreted in many ways. What it signifies depends on 
what the particular historian regards as being essential to 
philosophy.
This was true of Aristotle, who was philosophy’s first historian, 
and of Hegel, who hoped he would be its last, since he was 
bringing philosophy to perfection. The two of them had very 
different views of the nature of philosophy. Nonetheless, they 
had in common a view of philosophical progress: philosophical 
problems in the course of history became ever more clearly 
defined, and they could be answered with ever greater accuracy. 
Aristotle in the first book of his Metaphysics and Hegel in his 
Lectures on the History of Philosophy saw the teachings of the 
earlier philosophers they recorded as halting steps in the 
direction of a vision they were themselves to expound.
Only someone with supreme self-confidence as a philosopher 
could write its history in such a way. The temptation for most 
philosopher historians is to see philosophy not as culminating in 
their own work, but rather as a gradual progress to whatever 
philosophical system is currently
INTRODUCTION
in fashion. But this temptation should be resisted. There is no 
force that guarantees philosophical progress in any particular 
direction.
Indeed, it can be called into question whether philosophy makes 
any progress at all. The major philosophical problems, some say, 
are all still being debated after centuries of discussion, and are 
no nearer to any definitive resolution. In the twentieth century 
the philosopher Ludwig Wittgenstein wrote:
You always hear people say that philosophy makes no progress and 
that the same philosophical problems which were already preoccupying 
the Greeks are still troubling us today. But people who say that do not 
understand the reason why it has to be so. The reason is that our 
language has remained the same and always introduces us to the same 
questions. ...I read ‘philosophers are no nearer to the meaning 
of‘‘reality’’ than Plato got’. What an extraordinary thing! How 
remarkable that Plato could get so far! Or that we have not been able 
to get any further! Was it because Plato was so clever? (MS 213/424)
The difference between what we might call the Aristotelian and 
the Wittgensteinian attitude to progress in philosophy is linked 
with two different views of philosophy itself. Philosophy may be 
viewed as a science, on the one hand, or as an art, on the other. 
Philosophy is, indeed, uniquely difficult to classify, and 
resembles both the arts and the sciences.
On the one hand, philosophy seems to be like a science in that 
the philosopher is in pursuit of truth. Discoveries, it seems, are 
made in philosophy, and so the philosopher, like the scientist, 
has the excitement of belonging to an ongoing, cooperative, 
cumulative intellectual venture. If so, the philosopher must be 
familiar with current writing, and keep abreast of the state of the 
art. On this view, we twenty-first-century philosophers have an 
advantage over earlier practitioners of the discipline. We stand, 
no doubt, on the shoulders of other and greater philosophers, 
but we do stand above them. We have superannuated Plato and 
Kant.
On the other hand, in the arts, classic works do not date. If we 
want to learn physics or chemistry, as opposed to their history, 
we don’t nowadays read Newton or Faraday. But we read the 
literature of Homer and Shakespeare not merely to learn about 
the quaint things that passed through people’s minds in far-off 
xii
days of long ago. Surely, it may well be argued, the same is true 
of philosophy. It is not merely in a spirit of antiquarian curiosity 
that we read Aristotle today. Philosophy is essentially the work
INTRODUCTION
of individual genius, and Kant does not supersede Plato any 
more than Shakespeare supersedes Homer.
There is truth in each of these accounts, but neither is wholly 
true and neither contains the whole truth. Philosophy is not a 
science, and there is no state of the art in philosophy. 
Philosophy is not a matter of expanding knowledge, of acquiring 
new truths about the world; the philosopher is not in possession 
of information that is denied to others. Philosophy is not a 
matter of knowledge, it is a matter of understanding, that is to 
say, of organizing what is known. But because philosophy is all-
embracing, is so universal in its field, the organization of 
knowledge it demands is something so difficult that only genius 
can do it. For all of us who are not geniuses, the only way in 
which we can hope to come to grips with philosophy is by 
reaching up to the mind of some great philosopher of the past.
Though philosophy is not a science, throughout its history it has 
had an intimate relation to the sciences. Many disciplines that in 
antiquity and in the Middle Ages were part of philosophy have 
long since become independent sciences. A discipline remains 
philosophical as long as its concepts are unclarified and its 
methods are controversial. Perhaps no scientific concepts are 
ever fully clarified, and no scientific methods are ever totally 
uncontroversial; if so, there is always a philosophical element 
left in every science. But once problems can be 
unproblematically stated, when concepts are uncontroversially 
standardized, and where a consensus emerges for the 
methodology of solution, then we have a science setting up 
home independently, rather than a branch of philosophy.
Philosophy, once called the queen of the sciences, and once 
called their handmaid, is perhaps better thought of as the 
womb, or the midwife, of the sciences. But in fact sciences 
emerge from philosophy not so much by parturition as by 
fission. Two examples, out of many, may serve to illustrate this.
In the seventeenth century philosophers were much exercised 
by the problem which of our ideas are innate and which are 
acquired. This problem split into two problems, one 
psychological (‘What do we owe to heredity and what do we owe 
to environment?’) and one belonging to the theory of knowledge 
(‘How much of our knowledge depends on experience and hoxwiii 
much is independent of it?’). The first question was handed over 
to scientific psychology, the second question remained 
philosophical.
INTRODUCTION
But the second question itself split into a number of questions, 
one of which was ‘Is mathematics merely an extension of logic, 
or is it an independent body of truth?’ The question whether 
mathematics could be derived from pure logic was given a 
precise answer by the work of logicians and mathematicians in 
the twentieth century. The answer was not philosophical, but 
mathematical. So here we had an initial, confused, philosophical 
question which ramified in two directions—towards psychology 
and towards mathematics. There remains in the middle a 
philosophical residue to be churned over, concerning the nature 
of mathematical propositions.
An earlier example is more complicated. A branch of philosophy 
given an honoured place by Aristotle is ‘theology’. When today 
we read what he says, the discipline appears a mixture of 
astronomy and philosophy of religion. Christian and Muslim 
Aristotelians added to it elements drawn from the teaching of 
their sacred books. It was when St Thomas Aquinas, in the 
thirteenth century, drew a sharp distinction between natural and 
revealed theology that the first important fission took place, 
removing from the philosophical agenda the appeals to 
revelation. It took rather longer for the astronomy and the 
natural theology to separate out from each other. This example 
shows that what may be sloughed off by philosophy need not be 
a science but may be a humanistic discipline such as biblical 
studies. It also shows that the history of philosophy contains 
examples of fusion as well as of fission.
Philosophy resembles the arts in having a significant relation to 
a canon. A philosopher situates the problems to be addressed by 
reference to a series of classical texts. Because it has no specific 
subject matter, but only characteristic methods, philosophy is 
defined as a discipline by the activities of its great practitioners. 
The earliest people whom we recognize as philosophers, the 
Presocratics, were also scientists, and several of them were also 
religious leaders. They did not yet think of themselves as 
belonging to a common profession, the one with which we 
twenty-first-century philosophers claim continuity. It was Plato 
who in his writings first used the word ‘philosophy’ in some 
approximation to our modern sense. Those of us who call 
oxiuvrselves philosophers today can genuinely lay claim to be the 
heirs of Plato and Aristotle. But we are only a small subset of 
their heirs. What distinguishes us from the other heirs of the 
great Greeks, and what entitles us to inherit their name, is that 
unlike the physicists, the astronomers, the medics, the linguists, 
we phil¬
INTRODUCTION
osophers pursue the goals of Plato and Aristotle only by the 
same methods as were already available to them.
If philosophy lies somewhere between the sciences and the arts, 
what is the answer to the question ‘Is there progress in 
philosophy?’
There are those who think that the major task of philosophy is to 
cure us of intellectual confusion. On this, modest, view of the 
philosopher’s role, the tasks to be addressed differ across 
history, since each period needs a different form of therapy. The 
knots into which the undisciplined mind ties itself differ from age 
to age, and different mental motions are necessary to untie the 
knots. A prevalent malady of our own age, for instance, is the 
temptation to think of the mind as a computer, whereas earlier 
ages were tempted to think of it as a telephone exchange, a 
pedal organ, a homunculus, or a spirit. Maladies of earlier ages 
may be dormant, such as belief that the stars are living beings; 
or they may return, such as the belief that the stars enable one 
to predict human behaviour.
The therapeutic view of philosophy, however, may seem to allow 
only for variation over time, not for genuine progress. But that is 
not necessarily true. A confusion of thought may be so 
satisfactorily cleared up by a philosopher that it no longer offers 
temptation to the unwary thinker. One such example will be 
considered at length in the first volume of this history. 
Parmenides, the founder of the discipline of ontology (the 
science of being), based much of his system on a systematic 
confusion between different senses of the verb ‘to be’. Plato, in 
one of his dialogues, sorted out the issues so successfully that 
there has never again been an excuse for mixing them up: 
indeed, it now takes a great effort of philosophical imagination 
to work out exactly what led Parmenides into confusion in the 
first place.
Progress of this kind is often concealed by its very success: once 
a philosophical problem is resolved, no one regards it as any 
more a matter of philosophy. It is like treason in the epigram: 
‘Treason doth never prosper, what’s the reason? | For if it 
prosper none dare call it treason.’
The most visible form of philosophical progress is progress in 
philosophical analysis. Philosophy does not progress by makixnvg 
regular additions to a quantum of information; as has been said, 
what philosophy offers is not information but understanding. 
Contemporary philosophers, of course, know some things that 
the greatest philosophers of the past did not know; but the 
things that they know are not philosophical matters but the 
truths
INTRODUCTION
that have been discovered by the sciences begotten of 
philosophy. But there are also some things that philosophers of 
the present day understand which even the greatest 
philosophers of earlier generations failed to understand. For 
instance, philosophers clarify language by distinguishing 
between different senses of words; and once a distinction has 
been made, future philosophers have to take account of it in 
their deliberations.
Take, as an example, the issue of free will. At a certain point in 
the history of philosophy a distinction was made between two 
kinds of human freedom: liberty of indifference (ability to do 
otherwise) and liberty of spontaneity (ability to do what you 
want). Once this distinction has been made the question ‘Do 
human beings enjoy freedom of the will?’ has to be answered in 
a way that takes account of the distinction. Even someone who 
believes that the two kinds of liberty coincide has to provide 
arguments to show this; he cannot simply ignore the distinction 
and hope to be taken seriously on the topic.
It is unsurprising, given the relationship of philosophy to a 
canon, that one notable form of philosophical progress consists 
in coming to terms with, and interpreting, the thoughts of the 
great philosophers of the past. The great works of the past do 
not lose their importance in philosophy— but their intellectual 
contributions are not static. Each age interprets and applies 
philosophical classics to its own problems and aspirations. This 
is, in recent years, most visible in the field of ethics. The ethical 
works of Plato and Aristotle are as influential in moral thinking 
today as the works of any twentieth-century moralists—this is 
easily verified by taking any citation index—but they are being 
interpreted and applied in ways quite different from the ways in 
which they were applied in the past. These new interpretations 
and applications do effect a genuine advance in our 
understanding of Plato and Aristotle; but of course it is 
understanding of quite a different kind from what is given by a 
new study of the chronology of Plato’s dialogues or a stylometric 
comparison between Aristotle’s various ethical works. The new 
light we receive resembles rather the enhanced appreciation of 
Shakespeare we may get by seeing a new and intelligent 
pxvroi duction of King Lear.
The historian of philosophy, whether primarily interested in 
philosophy or primarily interested in history, cannot help being 
both a philosopher and a historian. A historian of painting does 
not have to be a painter; a historian of medicine does not, qua 
historian, practise medicine. But a
INTRODUCTION
historian of philosophy cannot help doing philosophy in the very 
writing of history. It is not just that someone who knows no 
philosophy will be a bad historian of philosophy; it is equally true 
that someone who has no idea of how to cook will be a bad 
historian of cookery. The link between philosophy and its history 
is a far closer one. The historical task itself forces historians of 
philosophy to paraphrase their subjects’ opinions, to offer 
reasons why past thinkers held the opinions they did, to 
speculate on the premisses left tacit in their arguments, and to 
evaluate the coherence and cogency of the inferences they 
drew. But the supplying of reasons for philosophical conclusions, 
the detection of hidden premisses in philosophical arguments, 
and the logical evaluation of philosophical inferences are 
themselves full-blooded philosophical activities. Consequently, 
any serious history of philosophy must itself be an exercise in 
philosophy as well as in history.
On the other hand, the historian of philosophy must have a 
knowledge of the historical context in which past philosophers 
wrote their works. When we explain historical actions, we ask for 
the agent’s reasons; if we find a good reason, we think we have 
understood his action. If we conclude he did not have good 
reason, even in his own terms, we have to find, different, more 
complicated explanations. What is true of action is true of taking 
a philosophical view. If the philosophical historian finds a good 
reason for a past philosopher’s doctrine, then his task is done. 
But if he concludes that the past philosopher has no good 
reason, he has a further and much more difficult task, of 
explaining the doctrine in terms of the context in which it 
appeared—social, perhaps, as well as intellectual.1
History and philosophy are closely linked even in the first-hand 
quest for original philosophical enlightenment. In modern times 
this has been most brilliantly illustrated by the masterpiece of 
the great nineteenth-century German philosopher Gottlob Frege, 
The Foundations of Arithmetic. Almost half of Frege’s book is 
devoted to discussing and refuting the view of other 
philosophers and mathematicians. While he is discussing the 
1 The magnitude of this task is well brought out by Michael Frede in 
tohpei ninitornosd uocft iotnh teor sh,i sh Ees seanyss uinr eAnsc tiehnat tP hsiolomsoep hoyf ( Ohixsf oorwd:n C ilnarseigndhotsn  are 
Parretsfus,l l1y9 87in).sinuated, and this makes easier the eventual 
presentation of his own theory. But the main purpose of xhviiis 
lengthy polemic is to convince readers of the seriousness of the 
problems to which he will later offer solutions. 1
INTRODUCTION
Without this preamble, he says, we would lack the first 
prerequisite for learning anything: knowledge of our own 
ignorance.
Most histories of philosophy, in this age of specialization, are the 
work of many hands, specialists in different fields and periods. In 
inviting me to write, single-handed, a history of philosophy from 
Thales to Derrida, Oxford University Press gave expression to the 
belief that there is something to be gained by presenting the 
development of philosophy from a single viewpoint, linking 
ancient, medieval, early modern, and contemporary philosophy 
into a single narrative concerned with connected themes. The 
work will appear in four volumes: the first will cover the 
centuries from the beginning of philosophy up to the conversion 
of St Augustine in ad 387. The second will take the story from 
Augustine up to the Lateran Council of 1512. The third will end 
with the death of Hegel in 1831. The fourth and final volume will 
bring the narrative up to the end of the second millennium.
Obviously, I cannot claim to be an expert on all the many 
philosophers whom I will discuss in the volumes of this work. 
However, I have published books on major figures within each of 
the periods of the four volumes: on Aristotle (The Aristotelian 
Ethics and Aristotle on the Perfect Life), on Aquinas (Aquinas on 
Mind and Aquinas on Being), on Descartes (Descartes: A Study 
of his Philosophy and Descartes: Philosophical Letters), and on 
Frege and Wittgenstein (Frege and Wittgenstein as Penguin 
introductions and The Legacy of Wittgenstein). I hope that the 
work that went into the writing of these books gave me an 
insight into the philosophical style of four different eras in the 
history of philosophy. It certainly gave me a sense of the 
perennial importance of certain philosophical problems and 
insights.
I hope to write my history in a manner that takes account of the 
points I have raised in this Introduction. I do not suffer from any 
Whiggish illusion that the current state of philosophy represents 
the highest point of philosophical endeavour yet reached. On the 
contrary, my primary purpose in writing the book is to show that 
in many respects the philosophy of the great dead philosophers 
has not dated, and that today one may gain philosophical 
xilvluiimi ination by a careful reading of the great works that we have 
been privileged to inherit.
The kernel of any kind of historiography of philosophy is 
exegesis: the close reading and interpretation of philosophical 
texts. Exegesis may be of two kinds, internal or external. In 
internal exegesis the interpreter tries to
INTRODUCTION
render the text coherent and consistent, making use of the 
principle of charity in interpretation. In external exegesis the 
interpreter seeks to bring out the significance of the text by 
comparing it and contrasting it with other texts.
Exegesis may form the basis of the two quite different historical 
endeavours that I described at the beginning of this 
Introduction. In one, which we may call historical philosophy, the 
aim is to reach philosophical truth, or philosophical 
understanding, about the matter or issue under discussion in the 
text. Typically, historical philosophy looks for the reasons 
behind, or the justification for, the statements made in the text 
under study. In the other endeavour, the history of ideas, the 
aim is not to reach the truth about the matter in hand, but to 
reach the understanding of a person or an age or a historical 
succession. Typically the historian of ideas looks not for the 
reasons so much as the sources, or causes, or motives, for 
saying what is said in the target text.
Both of these disciplines base themselves on exegesis, but of 
the two, the history of ideas is the one most closely bound up 
with the accuracy and sensitivity of the reading of the text. It is 
possible to be a good philosopher while being a poor exegete. At 
the beginning of his Philosophical Investigations Wittgenstein 
offers a discussion of St Augustine’s theory of language. What he 
writes is very dubious exegesis; but this does not weaken the 
force of his philosophical criticism of the ‘Augustinian’ theory of 
language. But Wittgenstein did not really think of himself as 
engaged in historical philosophy, any more than he thought of 
himself as engaged in the historiography of ideas. The 
invocation of the great Augustine as the author of the mistaken 
theory is intended merely to indicate that the error is one that is 
worth attacking.
In different histories of philosophy the skills of the historian and 
those of the philosopher are exercised in different proportions. 
The due proportion varies in accordance with the purpose of the 
work and the field of philosophy in question. The pursuit of 
historical understanding and the pursuit of philosophical 
enlightenment are both legitimate approaches to the history of 
philosophy, but both have their dangers. Historians who study 
the history of thought without being themselves involved in txhixe 
philosophical problems that exercised past philosophers are 
likely to sin by superficiality. Philosophers who read ancient, 
medieval, or early modern texts without a knowledge of the 
historical context in which they were
INTRODUCTION
written are likely to sin by anachronism. Rare is the historian of 
philosophy who can tread firmly without falling into either trap.
Each of these errors can nullify the purpose of the enterprise. 
The historian who is unconcerned by the philosophical problems 
that troubled past writers has not really understood how they 
themselves conducted their thinking. The philosopher who 
ignores the historical background of past classics will gain no 
fresh light on the issues that concern us today, but merely 
present contemporary prejudices in fancy dress.
The two dangers threaten in different proportions in different 
areas of the history of philosophy. In the area of metaphysics it 
is superficiality which is most to be guarded against: to someone 
without a personal interest in fundamental philosophical 
problems the systems of the great thinkers of the past will seem 
only quaint lunacy. In political philosophy the great danger is 
anachronism: when we read Plato’s or Aristotle’s criticisms of 
democracy, we shall not make head or tail of them unless we 
know something about the institutions of ancient Athens. In 
between metaphysics and political philosophy stand ethics and 
philosophy of mind: here both dangers threaten with roughly 
equal force.
I shall attempt in these volumes to be both a philosophical 
historian and a historical philosopher. Multi-authored histories 
are sometimes structured chronologically and sometimes 
structured thematically. I shall try to combine both approaches, 
offering in each volume first a chronological survey, and then a 
thematic treatment of particular philosophical topics of abiding 
importance. The reader whose primary interest is historical will 
focus on the chronological survey, referring where necessary to 
the thematic sections for amplification. The reader who is more 
concerned with the philosophical issues will concentrate rather 
on the thematic sections of the volumes, referring back to the 
chronological surveys to place particular issues in context.
Thus in this first volume I offer in the first part a conventional 
chronological tour from Pythagoras to Augustine, and in the 
second part a more detailed treatment of topics where I believe 
we have still much to learn from our predecessors in classical 
Greece and imperial Rome. The topics of these thematic sections 
xhxave been chosen partly with an eye to the development of the 
same themes in the volumes that are yet to come.
INTRODUCTION
The audience I have in mind is at the level of second- or third-
year undergraduate study. I realize, however, that many of 
those interested in the history of philosophy may themselves be 
enrolled in courses that are not primarily philosophical. 
Accordingly, I shall do my best not to assume a familiarity with 
contemporary philosophical techniques or terminology. I aim 
also to write in a manner clear and light-hearted enough for the 
history to be enjoyed by those who read it not for curricular 
purposes but for their own enlightenment and entertainment.
xxi
1
Beginnings:
From Pythagoras to 
Plato
The history of philosophy does not begin with Aristotle, but 
the historiography of philosophy does. Aristotle was the first 
philosopher who systematically studied, recorded, and criticized 
the work of previous philosophers. In the first book of the 
Metaphysics he summarizes the teachings of his predecessors, 
from his distant intellectual ancestors Pythagoras and Thales up 
to Plato, his teacher for twenty years. To this day he is one of 
the most copious, and most reliable, sources of our information 
about philosophy in its infancy.
The Four Causes
Aristotle offers a classification of the earliest Greek philosophers 
in accordance with the structure of his system of the four 
causes. Scientific inquiry, he believed, was above all inquiry into 
the causes of things; and there were four different kinds of 
cause: the material cause, the efficient cause, the formal cause, 
and the final cause. To give a crude illustration of what he had 
in mind: when Alfredo cooks a risotto, the material causes of the 
risotto are the ingredients that go into it, the efficient cause is 
the chef himself, the recipe is the formal cause, and the 
satisfaction of the clients of his restaurant is the final cause. 
Aristotle believed that a scientific understanding of the universe 
demanded an inquiry into the operation in the world of causes of 
each of these kinds (Metaph. A 3. 983a24-b17).
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Early philosophers on the Greek coast of Asia Minor 
concentrated on the material cause: they sought the basic 
ingredients of the world we live in. Thales and his successors 
posed the following question: At a fundamental level is the world 
made out of water, or air, or fire, or earth, or a combination of 
some or all of these? (Metaph. A 3. 983b20—84a16). Even if we 
have an answer to this question, Aristotle thought, that is clearly 
not enough to satisfy our scientific curiosity. The ingredients of a 
dish do not put themselves together: there needs to be an agent 
operating upon them, by cutting, mixing, stirring, heating, or the 
like. Some of these early philosophers, Aristotle tells us, were 
aware of this and offered conjectures about the agents of 
change and development in the world. Sometimes it would be 
one of the ingredients themselves—fire was perhaps the most 
promising suggestion, as being the least torpid of the elements. 
More often it would be some agent, or pair of agents, both more 
abstract and more picturesque, such as Love or Desire or Strife, 
or the Good and the Bad (Metaph. A 3-4. 984b8-31).
Meanwhile in Italy—again according to Aristotle—there were, 
around Pythagoras, mathematically inclined philosophers whose 
inquiries took quite a different course. A recipe, besides naming 
ingredients, will contain a lot of numbers: so many grams of this, 
so many litres of that. The Pythagoreans were more interested in 
the numbers in the world’s recipe than in the ingredients 
themselves. They supposed, Aristotle says, that the elements of 
numbers were the elements of all things, and the whole of the 
heavens was a musical scale. They were inspired in their quest 
by their discovery that the relationship between the notes of the 
scale played on a lyre corresponded to different numerical ratios 
between the lengths of the strings. They then generalized this 
idea that qualitative differences might be the upshot of 
numerical differences. Their inquiry, in Aristotle’s terms, was an 
inquiry into the formal causes of the universe. (Metaph. A 5. 
985b23-
986b2)
Coming to his immediate predecessors, Aristotle says that 
Socrates preferred to concentrate on ethics rather than study 
the world of nature, while Plato in his philosophical theory 
c2ombined the approaches of the schools of both Thales and 
Pythagoras. But Plato’s Theory of Ideas, while being the most 
comprehensive scientific system yet devised, seemed to 
Aristotle—for reasons that he summarizes here and develops in 
a number of his treatises—to be unsatisfactory on several 
grounds. There
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were so many things to explain, and the Ideas just added new 
items calling for explanation: they did not provide a solution, 
they added to the problem (Metaph. A 5. 990b1 ff.).
Most dissertations that begin with literature searches seek to 
show that all work hitherto has left a gap that will now be filled 
by the author’s original research. Aristotle’s Metaphysics is no 
exception. His not too hidden agenda is to show how previous 
philosophers neglected the remaining member of the quartet of 
causes: the final cause, which was to play a most significant role 
in his own philosophy of nature (Metaph. A 5. 988b6—15). The 
earliest philosophy, he concluded, is, on all subjects, full of 
babble, since in its beginnings it is but an infant (Metaph. A 5. 
993a15-7.)
A philosopher of the present day, reading the surviving 
fragments of the earliest Greek thinkers, is impressed not so 
much by the questions they were asking, as by the methods 
they used to answer them. After all, the book of Genesis offers 
us answers to the four causal questions set by Aristotle. If we 
ask for the origin of the first human being, for instance, we are 
told that the efficient cause was God, that the material cause 
was the dust of the earth, that the formal cause was the image 
and likeness of God, and that the final cause was for man to 
have dominion over the fish of the sea, the fowl of the air, and 
every living thing on earth. Yet Genesis is not a work of 
philosophy.
On the other hand, Pythagoras is best known not for answering 
any of the Aristotelian questions, but for proving the theorem 
that the square on the hypotenuse of a right-angled triangle is 
equal in area to the sum of the squares on the other two sides. 
Thales, again, was believed by later Greeks to have been the 
first person to make an accurate prediction of an eclipse, in the 
year 585 bc. These are surely achievements in geometry and 
astronomy, not philosophy.
The fact is that the distinction between religion, science, and 
philosophy was not as clear as it became in later centuries. The 
works of Aristotle and his master Plato provide a paradigm of 
philosophy for every age, and to this day anyone using the title 
‘philosopher’ is claiming to be one of their heirs. Writers in 
twenty-first-century philosophy journals can be seen to be usin3g 
the same techniques of conceptual analysis, and often to be 
repeating or refuting the same theoretical arguments, as are to 
be found in the writings of Plato and Aristotle. But in those 
writings there is much else that would
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not nowadays be thought of as philosophical discussion. From 
the sixth century bc onwards elements of religion, science, and 
philosophy ferment together in a single cultural cauldron. From 
our distance in time philosophers, scientists, and theologians 
can all look back to these early thinkers as their intellectual 
forefathers.
The Milesians
Only two sayings are recorded of Thales of Miletus (c.625—545 
bc), traditionally the founding father of Greek philosophy. They 
illustrate the melange of science and religion, for one of them 
was ‘All things are full of gods’, and the other was ‘Water is the 
first principle of everything’. Thales was a geometer, the first to 
discover the method of inscribing a right-angled triangle in a 
circle; he celebrated this discovery by sacrificing an ox to the 
gods (D.L. 1. 24—5). He measured the height of the pyramids by 
measuring their shadows at the time of day when his own 
shadow was as long as he was tall. He put his geometry to 
practical use: having proved that triangles with one equal side 
and two equal angles are congruent, he used this result to 
determine the distance of ships at sea.
Thales also had a reputation as an astronomer and a 
meteorologist. In addition to predicting the eclipse, he is said to 
have been the first to show that the year contained 365 days, 
and to determine the dates of the summer and winter solstices. 
He studied the constellations and made estimates of the sizes of 
the sun and moon. He turned his skill as a weather forecaster to 
good account: foreseeing an unusually good olive crop, he took 
a lease on all the oil mills and made a fortune through his 
monopoly. Thus, Aristotle said, he showed that philosophers 
could easily be rich if they wished (Pol. 1.
11. 1259a6—18).
If half the stories current about Thales in antiquity are true, he 
was a man of many parts. But tradition’s portrait of him is 
ambiguous. On the one hand, he figures as a philosophical 
entrepreneur, and a political and military pundit. On the other 
hand, he became a byword for unworldly absent-mindedness. 
4Plato, among others, tells the following tale:
Thales was studying the stars and gazing into the sky, when he fell into 
a well, and a jolly and witty Thracian servant girl made fun of him, 
saying that he was crazy to
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know about what was up in the heavens while he could not see what 
was in front of him beneath his feet. (Theaetetus 174a)
An unlikely story went around that he had met his death by just 
such a fall while stargazing.
Thales was reckoned as one of the Seven Sages, or wise men, of 
Greece, on a par with Solon, the great legislator of Athens. He is 
credited with a number of aphorisms. He said that before a 
certain age it was too soon for a man to marry; and after that 
age it was too late. When asked why he had no children, he said 
‘Because I am fond of children.’
Thales’ remarks heralded many centuries of philosophical 
disdain for marriage. Anyone who makes a list of a dozen really 
great philosophers is likely to discover that the list consists 
almost entirely of bachelors. One plausible list, for instance, 
would include Plato, Augustine, Aquinas, Scotus, Descartes, 
Locke, Spinoza, Hume, Kant, Hegel, and Wittgenstein, none of 
whom were married. Aristotle is the grand exception that 
disproves the rule that marriage is incompatible with 
philosophy.
Even in antiquity people found it hard to understand Thales’ 
adoption of water as the ultimate principle of explanation. The 
earth, he said, rested on water like a log floating in a stream—
but then, asked Aristotle, what does the water rest on? (Cael. 2. 
13. 294a28—34). He went further and said that everything came 
from and was in some sense made out of water. Again, his 
reasons were obscure, and Aristotle could only conjecture that it 
was because all animals and plants need water to live, or 
because semen is moist (Metaph. A 3. 983b17—27).
It is easier to come to grips with the cosmology of Thales’ junior 
compatriot Anaximander of Miletus (d. c.547 Bc). We know 
rather more about his views, because he left behind a book 
entitled On Nature, written in prose, a medium just beginning to 
come into fashion. Like Thales he was credited with a number of 
original scientific achievements: the first map of the world, the 
first star chart, the first Greek sundial, and an indoor clock as 
well. He taught that the earth was cylindrical in shape, like a 
stumpy column no higher than a third of its diameter. Around 
the world were gigantic tyres full of fire; each tyre was 
punctured with a hole through which the fire could be seen from5  
outside, and the holes were the sun and moon and stars. 
Blockages in the holes accounted for eclipses of the sun and 
phases of the moon. The celestial fire which is nowadays
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Anaximander with his sundial, in a Roman mosaic
largely hidden was once a great ball of flame around the infant 
earth; when this ball exploded, the fragments grew tyres like 
bark around themselves.
Anaximander was much impressed by the way trees grow and 
shed their bark. He used the same analogy to explain the origin 
of human beings. Other animals, he observed, can look after 
themselves soon after birth, but humans need a long nursing. If 
humans had always been as they are now, the race would not 
have survived. In an earlier age, he conjectured, humans had 
spent their childhood encased in a prickly bark, so that they 
looked like fish and lived in water. At puberty they shed their 
6bark, and
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stepped out onto dry land, into an environment in which they 
could take care of themselves. Because of this, Anaximander, 
though not otherwise a vegetarian, recommended that we 
abstain from eating fish, as the ancestors of the human race 
(KRS 133—7).
Anaximander’s cosmology is more sophisticated than Thales’ in 
several ways. First of all, he does not look for something to 
support the earth: it stays where it is because it is equidistant 
from everything else and there is no reason why it should move 
in any direction rather than any other (DK 12 A11; Aristotle, 
Gael. 2. 13. 295b10).
Secondly, he thinks it is an error to identify the ultimate material 
of the universe with any of the elements we can see around us 
in the contemporary world, such as water or fire. The 
fundamental principle of things, he said, must be boundless or 
undefined (apeiron). Anaximander’s Greek word is often 
rendered as ‘the Infinite’, but that makes it sound too grand. He 
may or may not have thought that his principle extended for 
ever in space; what we do know is that he thought it had no 
beginning and no end in time and that it did not belong to any 
particular kind or class of things. ‘Everlasting stuff’ is probably 
as close a paraphrase as we can get. Aristotle was later to refine 
the notion into his concept of prime matter.1
Thirdly, Anaximander offered an account of the origin of the 
present world, and explained what forces had acted to bring it 
into existence, inquiring, as Aristotle would say, into the efficient 
as well as the material cause. He saw the universe as a field of 
competing opposites: hot and cold, wet and dry. Sometimes one 
of a pair of opposites is dominant, sometimes the other: they 
encroach upon each other and then withdraw, and their 
interchange is governed by a principle of reciprocity. As 
Anaximander put it poetically in his one surviving fragment, 
‘they pay penalty and render reparation to each other for their 
injustice under the arbitration of time’ (DK 12 B1). Thus, one 
surmises, in winter the hot and the dry make reparation to the 
cold and the wet for the aggression they committed in summer. 
Heat and cold were the i fiSerset C ho. f5  tbheelo wo. pposites to make their 
appearance, separating off from an original cosmic egg of the 
everlasting indeterminate stuff. From them developed the fir7e 
and earth which, we have seen, lay at the origin of our present 
cosmos.
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Anaximenes (fl. 546—525 Bc), a generation younger than 
Anaximander, was the last of the trio of Milesian cosmologists. 
In several ways he is closer to Thales than to Anaximander, but 
it would be wrong to think that with him science is going 
backwards rather than forwards. Like Thales, he thought that 
the earth must rest on something, but he proposed air, rather 
than water, for its cushion. The earth itself is flat, and so are the 
heavenly bodies. These, instead of rotating above and below us 
in the course of a day, circle horizontally around us like a bonnet 
rotating around a head (KRS 151—6). The rising and setting of 
the heavenly bodies is explained, apparently, by the tilting of 
the flat earth. As for the ultimate principle, Anaximenes found 
Anaximander’s boundless matter too rarefied a concept, and 
opted, like Thales, for a single one of the existing elements as 
fundamental, though again he opted for air rather than water.
In its stable state air is invisible, but when it is moved and 
condensed it becomes first wind and then cloud and then water, 
and finally water condensed becomes mud and stone. Rarefied 
air became fire, thus completing the gamut of the elements. In 
this way rarefaction and condensation can conjure everything 
out of the underlying air (KRS 140—1). In support of this claim 
Anaximenes appealed to experience, and indeed to experiment
—an experiment that the reader can easily carry out for herself. 
Blow on your hand, first with the lips pursed, and then from an 
open mouth: the first time the air will feel cold, and the second 
time hot. This, argued Anaximenes, shows the connection 
between density and temperature (KRS 143).
The use of experiment, and the insight that changes of 
quality are linked to changes of quantity, mark Anaximenes as a 
scientist in embryo. Only in embryo, however: he has no means 
of measuring the quantities he invokes, he devises no equations 
to link them, and his fundamental principle retains mythical and 
religious properties.2 Air is divine, and generates deities out of 
itself (KRS 144—6); air is our soul, and holds our bodies together 
(KRS 160).
The Milesians, then, are not yet real physicists, but neither 
2 See J. aBraer ntehse, yT hme Pyrtehs-omcratkice Prsh.il oTshopehye rhs,a rveev .n eodtn .y (eLto lnedfot nm: Ryothu tbleedhgien,d 1,9 b8u2)t,  46—8.
they are moving away from it. They are not true philosophers 
e8ither, unless by ‘philosophy’
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one simply means infant science. They make little use of 
conceptual analysis and the a priori argument that has been the 
stock-in-trade of philosophers from Plato to the present day. 
They are speculators, in whose speculations elements of 
philosophy, science, and religion mingle in a rich and heady 
brew.
The Pythagoreans
In antiquity Pythagoras shared with Thales the credit for 
introducing philosophy into the Greek world. He was born in 
Samos, an island off the coast of Asia Minor, about 570 bc. At the 
age of 40 he emigrated to Croton on the toe of Italy. There he 
took a leading part in the political affairs of the city, until he was 
banished in a violent revolution about 510 bc. He moved to 
nearby Metapontum, where he died at the turn of the century. 
During his time at Croton he founded a semireligious 
community, which outlived him until it was scattered about 450 
bc. He is credited with inventing the word ‘philosopher’: instead 
of claiming to be a sage or wise man (sophos) he modestly said 
that he was only a lover of wisdom (philosophos) (D.L. 8. 8). The 
details of his life are swamped in legend, but it is clear that he 
practised both mathematics and mysticism. In both fields his 
intellectual influence, acknowledged or implicit, was strong 
throughout antiquity, from Plato to Porphyry.
The Pythagoreans’ discovery that there was a relationship 
between musical intervals and numerical ratios led to the belief 
that the study of mathematics was the key to the understanding 
of the structure and order of the universe. Astronomy and 
harmony, they said, were sister sciences, one for the eyes and 
one for the ears (Plato, Rep. 530d). However, it was not until two 
millennia later that Galileo and his successors showed the sense 
in which it is true that the book of the universe is written in 
numbers. In the ancient world arithmetic was too entwined with 
number mysticism to promote scientific progress, and the 
genuine scientific advances of the period (such as Aristotle’s 
zoology or Galen’s medicine) were achieved without benefit of 
mathematics.
Pythagoras’ philosophical community at Croton was th9e 
prototype of many such institutions: it was followed by Plato’s 
Academy, Aristotle’s
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Pythagoras commending vegetarianism, as imagined by Rubens
Lyceum, Epicurus’ Garden, and many others. Some such 
communities were legal entities, and others less formal; some 
resembled a modern research institute, others were more like 
monasteries. Pythagoras’ associates held their property in 
common and lived under a set of ascetic and ceremonial rules: 
observe silence, do not break bread, do not pick up crumbs, do 
not poke the fire with a sword, always put on the right shoe 
before the left, and so on. The Pythagoreans were not, to begin 
with, complete vegetarians, but they avoided certain kinds of 
meat, fish, and poultry. Most famously, they were forbidden to 
eat beans (KRS 271—2, 275—6).
The dietary rules were connected with Pythagoras’ beliefs about 
the soul. It did not die with the body, he believed, but migrated 
elsewhere, perhaps into an animal body of a different kind.3 
Some Pythagoreans extended this into belief in a three-
thousand-year cosmic cyc3 lSee: e aC hh. 7u mbealonw .soul after death would 
enter, one after the other, every kind of land, sea, or
10
PYTHAGORAS TO PLATO
air creature, and finally return into a human body for history to 
repeat itself (Herodotus 2. 123; KRS 285). Pythagoras himself, 
however, after his death was believed by his followers to have 
become a god. They wrote biographies of him full of wonders, 
crediting him with second sight and the gift of bilocation; he had 
a golden thigh, they said, and was the son of Apollo. More 
prosaically, the expression ‘Ipse dixit’ was coined in his honour.
Xenophanes
The death of Pythagoras, and the destruction of Miletus in 494, 
brought to an end the first era of Presocratic thought. In the next 
generation we encounter thinkers who are not only would-be 
scientists, but also philosophers in the modern sense of the 
word. Xenophanes of Colophon (a town near present-day Izmir, 
some hundred miles north of Miletus) straddles the two eras in 
his long life (c.570—c.470 Bc). He is also, like Pythagoras, a link 
between the eastern and the western centres of Greek cultures. 
Expelled from Colophon in his twenties, he became a wandering 
minstrel, and by his own account travelled around Greece for 
sixty-seven years, giving recitals of his own and others’ poems 
(D.L. 9. 18). He sang of wine and games and parties, but it is his 
philosophical verses that are most read today.
Like the Milesians, Xenophanes propounded a cosmology. The 
basic element, he maintained, was not water nor air, but earth, 
and the earth reaches down below us to infinity. ‘All things are 
from earth and in earth all things end’ (D.K. 21 B27) calls to 
mind Christian burial services and the Ash Wednesday 
exhortation ‘remember, man, thou art but dust and unto dust 
thou shalt return’. But Xenophanes elsewhere links water with 
earth as the original source of things, and indeed he believed 
that our earth must at one time have been covered by the sea. 
This is connected with the most interesting of his contributions 
to science: the observation of the fossil record.
Seashells are found well inland, and on mountains too, and in the 
quarries in Syracuse impressions of fish and seaweed have been found. 
An impression of a bay leaf was found in Paros deep in a rock, and in 
Malta there are flat shapes of all kinds of sea creatures. These were 
produced when everything was covered with mud long ago, and t1h1e 
impressions dried in the mud. (KRS 184)
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Xenophanes’ speculations about the heavenly bodies are less 
impressive. Since he believed that the earth stretched beneath 
us to infinity, he could not accept that the sun went below the 
earth when it set. On the other hand, he found implausible 
Anaximenes’ idea of a horizontal rotation around a tilting earth. 
He put forward a new and ingenious explanation: the sun, he 
maintained, was new every day. It came into existence each 
morning from a congregation of tiny sparks, and later vanished 
off into infinity. The appearance of circular movement is due 
simply to the great distance between the sun and ourselves. It 
follows from this theory that there are innumerable suns, just as 
there are innumerable days, because the world lasts for ever 
even though it passes through aqueous and terrestrial phases 
(KRS 175, 179).
Though Xenophanes’ cosmology is ill-founded, it is notable for 
its naturalism: it is free from the animist and semi-religious 
elements to be found in other Presocratic philosophers. The 
rainbow, for instance, is not a divinity (like Iris in the Greek 
pantheon) nor a divine sign (like the one seen by Noah). It is 
simply a multicoloured cloud (KRS 178). This naturalism did not 
mean that Xenophanes was uninterested in religion: on the 
contrary, he was the most theological of all the Presocratics. But 
he despised popular superstition, and defended an austere and 
sophisticated monotheism.4 He was not dogmatic, however, 
either in theology or in physics.
God did not tell us mortals all when time began
Only through long-time search does knowledge come to man.
(KRS 188)
Heraclitus
Heraclitus was the last, and the most famous, of the early Ionian 
philosophers. He was perhaps thirty years younger than 
Xenophanes, since he is reported to have been middle-aged 
when the sixth century ended (D.L. 9. 1). He lived in the great 
metropolis of Ephesus, midway between Miletus and Colophon. 
We possess more substantial portions of his work than of any 
previous philosopher, but that does not mean we find him easier 
to 4 See Ch. 9 below.
12
PYTHAGORAS TO PLATO
understand. His fragments take the form of pithy, crafted prose 
aphorisms, which are often obscure and sometimes deliberately 
ambiguous. Heraclitus did not argue, he pronounced. His delphic 
style may have been an imitation of the oracle of Apollo which, 
in his own words, ‘neither speaks, nor conceals, but gestures’ 
(KRS 244). The many philosophers in later centuries who have 
admired Heraclitus have been able to give their own colouring 
to his paradoxical, chameleon-like dicta.
Even in antiquity Heraclitus was found difficult. He was 
nicknamed ‘the Enigmatic One’ and ‘Heraclitus the Obscure’ 
(D.L. 9. 6). He wrote a three-book treatise on philosophy—now 
lost—and deposited it in the great temple of Artemis (St Paul’s 
‘Diana of the Ephesians’). People could not make up their minds 
whether it was a text of physics or a political tract. ‘What I 
understand of it is excellent,’ Socrates is reported as saying. 
‘What I don’t understand may well be excellent also; but only a 
deep sea diver could get to the bottom of it’ (D.L. 2. 22). The 
nineteenth-century German idealist Hegel, who was a great 
admirer of Heraclitus, used the same marine metaphor to 
express an opposite judgement. When we reach Heraclitus after 
the fluctuating speculations of the earlier Presocratics, Hegel 
wrote, we come at last in sight of land. He went on to add, 
proudly, ‘There is no proposition of Heraclitus which I have not 
adopted in my own Logic.’5
Heraclitus, like Descartes and Kant in later ages, saw himself as 
making a completely new start in philosophy. He thought the 
work of previous thinkers was worthless: Homer should have 
been eliminated at an early stage of any poetry competition, 
and Hesiod, Pythagoras, and Xenophanes were merely 
polymaths with no real sense (D.L. 9. 1). But, again like 
Descartes and Kant, Heraclitus was more influenced by his 
predecessors than he realized. Like Xenophanes, he was highly 
critical of popular religion: offering blood sacrifice to purge 
oneself of blood guilt was like trying to wash off mud with mud. 
Praying to statues was like whispering in an empty house, and 
phallic5  Lpercotucreess soino nthse  Hainstdo ryD oiof nPhyisloisaocp hryit, eesd . wanedre t rsainms.p Ely.  Sd. iHsagludsatnien g 
(KRSa n2d4 F1.,  H2.4 S3im).pson (London: Routledge, 1968), 279.
Again like Xenophanes, Heraclitus believed that the sun was 
new every day (Aristotle, Mete. 2. 2355b13—14), and, lik1e3 
Anaximander, he thought the
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sun was constrained by a cosmic principle of reparation (KRS 
226). The ephemeral theory of the sun is indeed in Heraclitus 
expanded into a doctrine of universal flux. Everything, he said, is 
in motion, and nothing stays still; the world is like a flowing 
stream. If we step into the same river twice, we cannot put our 
feet twice into the same water, since the water is not the same 
two moments together (KRS 214). That seems true enough, but 
on the face of it Heraclitus went too far when he said that we 
cannot even step twice into the same river (Plato, Cra. 402a). 
Taken literally, this seems false, unless we take the criterion of 
identity for a river to be the body of water it contains rather 
than the course it flows. Taken allegorically, it is presumably a 
claim that everything in the world is composed of constantly 
changing constituents: if this is what is meant, Aristotle said, the 
changes must be imperceptible ones (Ph. 8. 3. 253b9 ff.). 
Perhaps this is what is hinted at in Heraclitus’ aphorism that 
hidden harmony is better than manifest harmony—the harmony 
being the underlying rhythm of the universe in flux (KRS 207). 
Whatever Heraclitus meant by his dictum, it had a long history 
ahead of it in later Greek philosophy.
A raging fire, even more than a flowing stream, is a paradigm of 
constant change, ever consuming, ever refuelled. Heraclitus 
once said that the world was an ever-living fire: sea and earth 
are the ashes of this perpetual bonfire. Fire is like gold: you can 
exchange gold for all kinds of goods, and fire can turn into any 
of the elements (KRS 217—19). This fiery world is the only world 
there is, not made by gods or men, but governed throughout by 
Logos. It would be absurd, he argued, to think that this glorious 
cosmos is just a piled-up heap of rubbish (DK 22 B124). ‘Logos’ 
is the everyday Greek term for a written or spoken word, but 
from Heraclitus onwards almost every Greek philosopher gave it 
one or more of several grander meanings. It is often rendered by 
translators as ‘Reason’—whether to refer to the reasoning 
powers of human individuals, or to some more exalted cosmic 
principle of order and beauty. The term found its way into 
Christian theology when the author of the fourth gospel 
proclaimed, ‘In the beginning was the Logos, and the Logos was 
with God, and the Logos was God’ (John 1: 1).
T1h4is universal Logos, Heraclitus says, is hard to grasp and most 
men never succeed in doing so. By comparison with someone 
who has woken up to the Logos, they are like sleepers curled up 
in their own dream-world instead of facing up to the single, 
universal truth (S.E., M. 7. 132). Humans
PYTHAGORAS TO PLATO
fall into three classes, at various removes from the rational fire 
that governs the universe. A philosopher like Heraclitus is 
closest to the fiery Logos and receives most warmth from it; 
next, ordinary people when awake draw light from it when they 
use their own reasoning powers; finally, those who are asleep 
have the windows of their soul blocked up and keep contact with 
nature only through their breathing (S.E., M. 7. 129—30).6 Is the 
Logos God? Heraclitus gave a typically quibbling answer. ‘The 
one thing that alone is truly wise is both unwilling and willing to 
be called by the name of Zeus.’ Presumably, he meant that the 
Logos was divine, but was not to be identified with any of the 
gods of Olympus.
The human soul is itself fire: Heraclitus sometimes lists soul, 
along with earth and water, as three elements. Since water 
quenches fire, the best soul is a dry soul, and must be kept from 
moisture. It is hard to know exactly what counts as moisture in 
this context, but alcohol certainly does: a drunk, Heraclitus says, 
is a man led by a boy (KRS 229—31). But Heraclitus’ use of ‘wet’ 
also seems close to the modern slang sense: brave and tough 
men who die in battle, for instance, have dry souls that do not 
suffer the death of water but go to join the cosmic fire (KRS 
237).7
What Hegel most admired in Heraclitus was his insistence on the 
coincidence of opposites, such as that the universe is both 
divisible and indivisible, generated and ungenerated, mortal and 
immortal. Sometimes these identifications of opposites are 
straightforward statements of the relativity of certain predicates. 
The most famous, ‘The way up and the way down are one and 
the same’, sounds very deep. However, it need mean no more 
than that when, skipping down a mountain, I meet you toiling 
upward, we are both on the same path. Different things are 
attractive at different times: food when you are hungry, bed 
when you are sleepy (KRS 201). Different things attract different 
species: sea-water is wholesome for fish, but poisonous for 
humans; donkeys prefer rubbish to gold (KRS 199).
Not all Heraclitus’ pairs of coinciding opposites admit of easy 
resolution by relativity, and even the most harmless-looking 
ones may have a more profound significance. Thus Diogenes 
Laertius tells us that the sequence fire—air—water—earth is th15e 
road downward, and the sequence earth— water-air—fire is the 
road upward (D.L. 9. 9—11). These two roads can
6    Readers of Plato are bound to be struck by the anticipation of the 
allegory of the Cave in the Republic.
7    See the discussion in KRS 208.
PYTHAGORAS TO PLATO
only be regarded as the same if they are seen as two stages on 
a continuous, everlasting, cosmic progress. Heraclitus did indeed 
believe that the cosmic fire went through stages of kindling and 
quenching (KRS 217). It is presumably also in this sense that we 
are to understand that the universe is both generated and 
ungenerated, mortal and immortal (DK 22 B50). The underlying 
process has no beginning and no end, but each cycle of kindling 
and quenching is an individual world that comes into and goes 
out of existence.
Though several of the Presocratics are reported to have been 
politically active, Heraclitus has some claim, on the basis of the 
fragments, to be the first to produce a political philosophy. He 
was not indeed interested in practical politics: an aristocrat with 
a claim to be a ruler, he waived his claim and passed on his 
wealth to his brother. He is reported to have said that he 
preferred playing with children to conferring with politicians. But 
he was perhaps the first philosopher to speak of a divine law—
not a physical law, but a prescriptive law, that trumped all 
human laws.
There is a famous passage in Robert Bolt’s play about Thomas 
More, A Man for AH Seasons. More is urged by his son-in-law 
Roper to arrest a spy, in contravention of the law. More refuses 
to do so: ‘I know what’s legal, not what’s right; and I’ll stick to 
what’s legal.’ More denies, in answer to Roper, that he is setting 
man’s law above God’s. ‘I’m not God,’ he says, ‘but in the 
thickets of the law, there I am a forester.’ Roper says that he 
would cut down every law in England to get at the Devil. More 
replies, ‘And when the last law was down, and the Devil turned 
round on you—where would you hide, Roper, the laws all being 
flat?’8
It is difficult to find chapter and verse in More’s own writings or 
recorded sayings for this exchange. But two fragments of 
Heraclitus express the sentiments of the participants. ‘The 
people must fight on behalf of the law as they would for the city 
wall’ (KRS 249). But though a city must rely on its law, it must 
place a much greater reliance on the universal law that is 
common to al8l.  R‘Aoblle trht eB olaltw, As oMfa nh ufomr Aalln Sse asroen sn (oLuornisdhoen:d H beyin ae msianngnl,e 1 960), 39.
law, the divine law’ (KRS 250).
W16hat survives of Heraclitus amounts to no more than 15,000 
words. The enormous influence he has exercised on 
philosophers ancient and modern is a matter for astonishment. 
There is something fitting about his position
PYTHAGORAS TO PLATO
in Raphael’s fresco in the Vatican stanze, The School of Athens. 
In this monumental scenario, which contains imaginary portraits 
of many Greek philosophers, Plato and Aristotle, as is right and 
just, occupy the centre stage. But the figure to which one’s eye 
is immediately drawn on entering the room is a late addition to 
the fresco: the booted, brooding figure of Heraclitus, deep in 
meditation on the lowest step.9
Parmenides and the Eleatics
In Roman times Heraclitus was known as ‘the weeping 
philosopher’. He was contrasted with the laughing philosopher, 
the atomist Democritus. A more appropriate contrast would be 
with Parmenides, the head of the Italian school of philosophy in 
the early fifth century. For classical Athens, Heraclitus was the 
proponent of the theory that everything was in motion, and 
Parmenides the proponent of the theory that nothing was in 
motion. Plato and Aristotle struggled, in different ways, to 
defend the audacious thesis that some things were in motion 
and some things were at rest.
Parmenides, according to Aristotle (Metaph. A 5. 986b21—5), 
was a pupil of Xenophanes, but he was too young to have 
studied under him in Colophon. He spent most of his life in Elea, 
seventy miles or so south of Naples. There he may have 
encountered Xenophanes on his wanderings. Like Xenophanes, 
he was a poet: he wrote a philosophical poem in clumsy verse, 
of which we possess about 120 lines. He is the first philosopher 
whose writing has come down to us in continuous fragments 
that are at all substantial.
The poem consists of a prologue and two parts, one called the 
path of truth, the other the path of mortal opinion. The prologue 
shows us the poet riding in a chariot with the daughters of the 
Sun, leaving behind the halls of night and travelling towards the 
light. They reach the gates which lead to the paths of night and 
day; it is not clear whether these are the same as the paths of 
truth and opinion. At all events, the goddess who welcomes him 
on his quest tells him that he must learn both:
9 The figure traditionally regarded as Heraclitus does not figure on 
cartoons for the fresco. Michelangelo is said to have been Raphael’s 
model, though R. Jones and N. Penny, Raphael, (London: Yale Universi1t7y 
Press, 1983) 77, doubt both traditions.
PYTHAGORAS TO PLATO
Besides trustworthy truth’s unquaking heart Learn the 
false fictions of poor mortals’ art.
(KRS 288. 29-30)
There are only two possible routes of inquiry:
Two ways there are of seeking how to see One that it is, 
and is not not to be—
That is the path of Truth’s companion Trust—
The other it is not, and not to be it must.    (KRS 291. 2-
5)
(I must ask the reader to believe that Parmenides’ 
Greek is as clumsy and as baffling as this English 
text.) Parmenides’ Way of Truth, thus riddlingly 
introduced, marks an epoch in philosophy. It is the 
founding charter of a new discipline: ontology or 
metaphysics, the science of Being.
Whatever there is, whatever can be thought of, is 
for Parmenides nothing other than Being. Being is 
one and indivisible: it has no beginning and no end, 
and it is not subject to temporal change. When a 
kettle of water boils away, this may be, in 
Heraclitus’ words, the death of water and the birth 
of air; but for Parmenides it is not the death or 
birth of Being. Whatever changes may take place, 
they are not changes from being to nonbeing; they 
are all changes within Being. But for Parmenides 
there are not, in fact, any real changes at all. Being 
is everlastingly the same, and time is unreal 
because past, present, and future are all one.10
The everyday world of apparent change is 
described in the second part of Parmenides’ poem, 
the Way of Seeming, which his goddess introduces 
thus:
I bring to an end my trusty word and thought,
The tale of Truth. The rest’s another sort—
A pack of lies expounding men’s beliefs.    (KRS 300)
It is not clear why Parmenides feels obliged to 
10A detailed examination of Parmenides’ ontology will be found in Ch. 6 below.
reproduce the false notions that are entertained by 
deluded mortals. If we took the second part of his 
18
poem out of its context, we would see in it a 
cosmology very much in the tradition of the Ionian 
thinkers. To the normal pairs of opposites 
Parmenides adds light and darkness, and he is 
given credit by Aristotle for introducing Love as the 
efficient cause of everything (Metaph. A 3. 984b27). 
The Way of Seeming in fact includes two truths not 
hitherto
PYTHAGORAS TO PLATO
generally known: first, that the earth is a sphere (D.L. 9. 21), and 
secondly, that the Morning Star is the same as the Evening Star. 
Parmenides’ disowned discovery was to provide philosophers of 
a later generation with a paradigm for identity statements.11
Parmenides had a pupil, Melissus, who came from Pythagoras’ 
island of Samos and who was said to have studied also with 
Heraclitus. He was active in politics, and rose to the rank of 
admiral of the Samos fleet. In 441 bc Samos was attacked by 
Athens, and though Athens was finally victorious in the war 
Melissus is recorded as having twice inflicted defeat on the fleet 
of Pericles (Plutarch, Pericles 166c—d; D.L. 9. 4).
Melissus expounded the philosophy of Parmenides’ poem in 
plain prose, arguing that the universe was unlimited, 
unchangeable, immovable, indivisible, and homogeneous. He 
was remembered for drawing two consequences from this 
monistic view: (1) pain was unreal, because it implied 
(impossibly) a deficiency of being; (2) there was no such thing as 
a vacuum, since it would have to be apiece of Unbeing. Local 
motion was therefore impossible, for the bodies that occupy 
space have no room to move into (KRS 534).
Another pupil of Parmenides was Zeno of Elea. He produced a 
set of more famous arguments against the possibility of motion. 
The first went like this: ‘There is no motion, for whatever moves 
must reach the middle of its course before it reaches the end.’ 
To get to the far end of a stadium, you have to run to the half-
way point, to get to the half-way point you must reach the point 
half-way to that, and so ad infinitum. Better known is the second 
argument, commonly known as Achilles and the tortoise. ‘The 
slower’, Zeno said, ‘will never be overtaken by the swifter, for 
the pursuer must first reach the point from which the fugitive 
departed, so that the slower must necessarily remain ahead.’ 
Let us suppose that Achilles runs four times as fast as the 
tortoise, and that the tortoise is given a forty-metre start when 
they run a hundred-metre race against each other. According to 
Zeno’s argument, Achilles can never win. For by the time he 
reaTchhee s1 9tthh-ec enfoturtryy- mpheiltorseo pmhearr Gk,o tttlhoeb  Ftroergteo iussee di st hea heexaamd pbley t ot einntr oduce his celebrated
mdisettirnecsti.o nB yb etthwee etnim sen sAec ahnildle rse fhearesn creu.n those ten, the tortoise is 
still ahead by two and a half metres. Each time Achilles makes 
up a gap, the tortoise opens up a new, shorter, gap, so he ca1n9 
never overtake him (Aristotle, Ph. 5. 9. 239b11—14).
PYTHAGORAS TO PLATO
These and other similar arguments of Zeno assume that 
distances and motions are infinitely divisible. His arguments 
have been dismissed by some philosophers as ingenious but 
sophistical paradoxes. Others have admired them greatly: 
Bertrand Russell, for instance, claimed that they provided the 
basis of the nineteenth-century mathematical renaissance of 
Weierstrass and Cantor.12 Aristotle, who preserved Zeno’s 
puzzles for us, claimed to disarm them, and to re-establish the 
possibility of motion, by distinguishing between two forms of 
infinity: actual infinity and potential infinity.B But it was not for 
many centuries that the issues raised by Zeno were given 
solutions that satisfied both philosophers and mathematicians.
Empedocles
The most flamboyant of the early philosophers of Greek Italy 
was Empedocles, who flourished in the middle of the fifth 
century. He was a native of Acragas, the town on the south 
coast of Sicily which is now Agrigento. The town’s port today 
bears the name Porto Empedocle, but this testifies not to an 
enduring veneration of the philosopher, but to the 
Risorgimento’s passion for renaming sites in honour of Italy’s 
past glories.
Empedocles came of an aristocratic family which owned a stud 
of prizewinning horses. In politics, however, he is reputed to 
have been a democrat; he is said to have foiled a plot to turn the 
city into a dictatorship. The grateful citizens, the story goes on, 
offered to make him king, but he refused the office, preferring 
his frugal life as a physician and counsellor (D.L. 8. 63). If free of 
ambition, however, he was not devoid of vanity, and in one of 
his poems he boasts that wherever he goes men and women 
throng to him for advice and healing. He claimed to possess 
drugs to ward off old age, and to know spells to control the 
weather. In the same poem he frankly professed himself to have 
achieved divine status (D.L. 8. 66).
Different biographical traditions, not all chronologically possible, 
make Empedocles a pupil of Pythagoras, of Xenophanes, and of 
Parmen iTdhees P. rinCceiprlteas ionfl yM athheem aimticist a(Lteodnd oPna:r Amlleenn i&de Usn wbiny,  1w9r0i3ti)n, g12 3 47a.     u See Ch. 5 below.
hexameter poem On Nature; this poem, dedicated to his friend 
P20ausanias, contained about 2,000 lines, of which we possess 
about a fifth. He also wrote a religious poem, Purifications,
PYTHAGORAS TO PLATO
of which less has been preserved. Scholars do not agree to 
which poem should be attached the many disjointed citations 
that survive; some, indeed, think that the two poems belonged 
to a single work. Further pieces of the textual jigsaw were 
recovered when forty papyrus fragments were identified in the 
archives of the University of Strasbourg in 1994. As a poet, 
Empedocles was more fluent than Parmenides, and also more 
versatile. According to Aristotle, he wrote an epic on Xerxes’ 
invasion of Greece, and according to other traditions he was the 
author of several tragedies (D.L. 8. 57).
Empedocles’ philosophy of nature can be regarded, from one 
point of view, as a synthesis of the thought of the Ionian 
philosophers. As we have seen, each of them had singled out 
some one substance as the basic or dominant stuff of the 
universe: Thales had privileged water, Anaximenes air, 
Xenophanes earth, and Heraclitus fire. For Empedocles all four of 
these substances stood on equal terms as the fundamental 
ingredients, or ‘roots’ as he put it, of the universe. These roots 
had always existed, he maintained, but they mingle with each 
other in various proportions in such a way as to produce the 
familiar fuFrrnomitu trhee soe ff otuhre s pwraonrgld w haantd w aasl saon dt hise a ndde envizeer nshsa lol:f the 
Trees, beasts, and human beings, males and females all,
heavens. Birds of the air, and fishes bred by water bright;
The age-old gods as well, long worshipped in the height.
These four are all there is, each other interweaving
And, intermixed, the world’s variety achieving.    (KRS 355)
What Empedocles called ‘roots’ were called by Plato 
and later Greek thinkers stoicheia, a word earlier used 
to indicate the syllables of a word. The Latin 
translation elementum, from which our ‘element’ is 
derived, compares the roots not to syllables, but to 
letters of the alphabet: an elementum is an LMNtum. 
Empedocles’ quartet of elements was assigned a 
fundamental role in physics and chemistry by 
philosophers and scientists until the time of Boyle in 
the seventeenth century. Indeed, it can be claimed 
that it is still with us, in altered form. Empedocles 
thought of his elements as four different kinds of 
matter; we think of solid, liquid, and gas as three 
21
states of matter. Ice, water, and steam would be, for 
Empedocles, specific instances of earth, water, and air; 
for us they are three different
PYTHAGORAS TO PLATO
states of the same substance, H2O. It was not unreasonable to 
think of fire, and especially the fire of the sun, as a fourth 
element of equal importance. One might say that the twentieth-
century emergence of the science of plasma physics, which 
studies the properties of matter at the sun’s temperature, has 
restored Empedocles’ fourth element to parity with the other 
three.
Aristotle praised Empedocles for having realized that a 
cosmological theory must not just identify the elements of the 
universe, but must assign causes for the development and 
intermingling of the elements to make the living and inanimate 
compounds of the actual world. Empedocles assigns this role to 
Love and Strife: Love combines the elements, and Strife forces 
them apart. At one time the roots grow to be one out of many, 
at another time they split to be many out of one. These things, 
he said, never cease their continual interchange, now through 
love coming together into one, now carried apart from each 
other by Strife’s hatred
(KRS 348).
Love and Strife are the picturesque ancestors of the forces of 
attraction and repulsion which have figured in physical theory 
throughout the ages. For Empedocles, history is a cycle in which 
sometimes Love is dominant, and sometimes Strife. Under the 
influence of Love the elements combine into a homogeneous, 
harmonious, and resplendent sphere, reminiscent of 
Parmenides’ universe. Under the influence of Strife the elements 
separate out, but when Love begins to regain the ground it had 
lost, all the different species of living beings appear (KRS 360). 
All compound beings, such as animals and birds and fish, are 
temporary creatures that come and go; only the elements are 
everlasting, and only the cosmic cycle goes on for ever.
To explain the origin of living species, Empedocles put forward a 
remarkable theory of evolution by survival of the fittest. First 
flesh and bone emerged as chemical mixtures of the elements, 
flesh being constituted by fire, air, and water in equal parts, and 
bone being two parts water to two parts earth and four parts 
fire. From these constituents unattached limbs and organs were 
formed: unsocketed eyes, arms without shoulders, and faces 
w22ithout necks (KRS 375—6). These roamed around until they 
chanced to find partners; they formed unions, which were often, 
at this preliminary stage, quite unsuitable. Thus there arose 
various monstrosities: human-headed oxen, ox-headed humans, 
androgynous creatures with
PYTHAGORAS TO PLATO
faces and breasts on front and back (KRS 379). Most of these 
fortuitous organisms were fragile or sterile; only the fittest 
structures survived to be the human and animal species we 
know. Their fitness to reproduce was a matter of chance, not 
design (Aristotle, Ph. 2. 8. 198b29).
Aristotle paid tribute to Empedocles for being the first to grasp 
the important biological principle that different parts of 
dissimilar living organisms might have homologous functions: 
e.g. olives and eggs, leaves and feathers (Aristotle, GA 1. 23. 
731a4). But he was contemptuous of his attempt to reduce 
teleology to chance, and for many centuries biologists followed 
Aristotle rather than Empedocles. Empedocles had the last laugh 
when Darwin saluted him for ‘shadowing forth the principle of 
natural selection’.14
Empedocles employed his quartet of elements in giving an 
account of sense-perception, based on the principle that like is 
known by like. In his poem Purifications he combined his 
physical theory with the Pythagorean doctrine of 
metempsychosis. 15 Sinners—divine or human—are punished 
when Strife casts their souls into different kinds of creatures on 
land and sea. A cycle of reincarnation held out a hope of 
eventual deification for privileged classes of men: seers, bards, 
doctors, and princes (KRS 409). Empedocles, of course, had a 
claim to identify himself with all these professions.
In his writing, Empedocles moves seamlessly between an 
austerely mechanistic mode and a mystically religious one. He 
sometimes uses divine names for his four elements (Zeus, Hera, 
Aidoneus, and Nestis) and identifies his Love with the goddess 
Aphrodite, whom he celebrates in terms anticipating Schiller’s 
great ‘Ode to Joy’ (KRS 349). No doubt his own claim to divinity 
can be deflated in the same way as he demythologizes the 
Olympian gods. But it caught the attention of posterity, 
especially in the legend of his death.
A woman called Pantheia, the story goes, given up for dead by 
the physicians, was miraculously restored to life by Empedocles. 
To celebrate, he offered a sacrificial banquet to eighty guests in 
a rich man’s house at the foot of Etna. When the other guests 
went to sleep, he heard his name called from heaven. He 
hastened to the summit of the volcano, and then, in Milton2’3s 
words,
14    Appendix to 6th edn. of The Origin of Species, quoted in A. Gottlieb, 
The Dream of Reason: A History of Western Philosophy from the Greeks to the 
Renaissance (London: Allen Lane, 2000), 80.
15    See Ch. 7 below.
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to be deemed
A god, leaped 
fondly into 
Aetna flames.
Matthew Arnold dramatized this s(Ptoarrayd iisne  Lhoisst  Empedocles on 
Etna. He places these verses in theI IIm. 4o7u0t)h of the philosopher at 
the crater’s rim:
This heart will glow no more; thou art A living man no 
more, Empedocles!
Nothing but a devouring flame of thought—
But a naked, eternally restless mind!
To the elements it came from Everything will return Our 
bodies to earth,
Our blood to water,
Heat to fire,
Breath to air.
They were well born, they will be well entomb’d—
But mind?
(lines 326—38)
Arnold gives the philosopher, before his Wnal leap, 
the hope that in reward for his love of truth his 
intellect will never wholly perish.
Anaxagoras
If Empedocles achieved a kind of immortality as a precursor of 
Darwin, his contemporary Anaxagoras is sometimes regarded as 
an intellectual ancestor of the currently popular cosmology of 
the big bang. Anaxagoras was born around 500 bc in 
Clazomenae, near Izmir, and was possibly a pupil of 
Anaximenes. After the end of the wars between Persia and 
Greece, he came to Athens and was a client of the statesman 
Pericles. He thus stands at the head of the distinguished series 
of philosophers whom Athens either bred or welcomed. When 
Pericles fell from favour, Anaxagoras too became a target of 
popular attack. He was prosecuted for treason and impiety, and 
Xed to Lampsacus on the Hellespont, where he lived in 
2h4onourable exile until his death in 428.
PYTHAGORAS TO PLATO
Here is his account of the beginning of the universe: ‘All 
things were together, infinite in number and infinite in 
smallness; for the small too was infinite. While all things were 
together, nothing was recognizable because of its smallness. 
Everything lay under air and ether, both infinite’ (KRS 467). This 
primeval pebble began to rotate, throwing off the surrounding 
ether and air and forming out of them the stars and the sun and 
the moon. The rotation caused the separation of dense from 
rare, of hot from cold, of dry from wet, and bright from dark. But 
the separation was never complete, and to this day there 
remains in every single thing a portion of everything else. There 
is a little whiteness in what is black, a little cold in what is hot, 
and so on: things are named after the item that is dominant in it 
(Aristotle, Ph. 1. 4. 187a23). This is most obvious in the case of 
semen, which must contain hair and flesh, and much, much 
more; but it must also be true of the food we eat (KRS 483—4, 
496). In this sense, as things were in the beginning, so now they 
are all together.
The expansion of the universe, Anaxagoras maintained, has 
continued in the present and will continue in the future (KRS 
476). Perhaps it has already generated worlds other than our 
own. As a result of the presence of everything in everything, he 
says,
men have been formed and the other ensouled animals. And the 
men possess farms and inhabit cities just as we do, and they have a 
sun and a moon and the rest just like us. The earth produces things of 
every sort for them to be harvested and stored, as it does for us. I have 
said all this about the process of separating oV, because it would have 
happened not only here with us, but elsewhere too. (KRS 498)
Anaxagoras thus has a claim to be the originator of the idea, 
later proposed by Giordano Bruno and popular again today in 
some quarters, that our cosmos is just one of many which may, 
like ours, be inhabited by intelligent creatures.
The motion that sets in train the development of the universe 
is, according to Anaxagoras, the work of Mind. ‘All things were 
together: then Mind came and gave them order’ (D.L. 2. 6). Mind 
is infinite and separate, and has no part in the general 
commingling of elements; if it did, it would get drawn into the 
evolutionary process and could not control it. This teaching, 
25
placing mind firmly in control of matter, so struck his 
contemporaries that they nicknamed Anaxagoras himself the
PYTHAGORAS TO PLATO
Mind. It is difficult, however, to assess exactly what his doctrine, 
though it greatly impressed both Plato and Aristotle, actually 
meant in practice.
In Plato’s dialogue Phaedo, Socrates, in his last days in prison, is 
made to express his gradual disillusionment with the 
mechanistic explanations of natural science to be found in the 
early philosophers. He was pleased, he said, when he heard that 
Anaxagoras had explained everything by nous, or mind; but he 
was disappointed by the total absence of reference to value in 
his work. Anaxagoras was like someone who said that all 
Socrates’ actions were performed with his intelligence, and then 
gave the reason why he was sitting here in prison by talking 
about the constitution of his body from bones and sinews, and 
the nature and properties of these parts, without mentioning 
that he judged it better to sit there in obedience to the Athenian 
court’s sentence. Teleological explanation was more profound 
than mechanistic explanation. ‘If anyone wants to find out the 
reason why each thing comes to be or perishes or exists, this is 
what he must find out about it: how is it best for that thing to 
exist, or to act or be acted upon in any way?’ (Phd. 97d).
Anaxagoras speaks about his Mind in ways appropriate to 
divinity, and this could have made him vulnerable to a charge, in 
the Athenian courts, of introducing strange gods. But in fact the 
charge of impiety seems to have been based on his scientific 
conjectures. The sun, he said, was a fiery lump of metal, 
somewhat larger than the Peloponnesus. This was taken to be 
incompatible with the veneration appropriate to the sun as 
divine. In exile in Lampsacus, Anaxagoras made his final 
benefaction to humanity: the invention of the school holiday. 
Asked by the authorities of the city how they should honour him, 
he said that children shouTlhd eb eA tleotm oisfft sschool in the month of his 
death. He had already earned the gratitude of students of 
Tschie nficnea bl ayn bde imngo stth set rfiirksint gw raintetirc tipoa inticolnu doef  mdioadgerarnm sc iine nhcise  tienx th. e 
Presoc-ratic era was made by Leucippus of Miletus and 
Democritus of Abdera. Though they are always named together, 
like Tweedledum and Tweedle-dee, and considered joint 
founders of atomism, nothing really is known about Leucippus 
except that he was the teacher of Democritus. It is on the
26
PYTHAGORAS TO PLATO
surviving writings of the latter that we principally depend for our 
knowledge of the theory. Democritus was a polymath and a 
prolific writer, author of nearly eighty treatises on topics ranging 
from poetry and harmony to military tactics and Babylonian 
theology. All these treatises are lost, but we do possess a 
copious collection of fragments from Democritus, more than 
from any previous philosopher.
Democritus was born in Abdera, on the coast of Thrace, and was 
thus the first significant philosopher to be born on the Greek 
mainland. The date of his birth is uncertain, but it was probably 
between 470 and 460 bc. He is reported to have been forty years 
younger than Anaxagoras, from whom he took some of his ideas. 
He travelled widely and visited Egypt and Persia, but was not 
over-impressed by the countries he visited. He once said that he 
would prefer to discover a single scientific explanation than to 
become king of Persia (D.L. 9. 41; DK 68 B118).
Democritus’ fundamental thesis is that matter is not infinitely 
divisible. We do not know his exact argument for this conclusion, 
but Aristotle conjectured that it ran as follows. If we take a 
chunk of any kind of stuff and divide it up as far as we can, we 
will have to come to a halt at tiny bodies which are indivisible. 
We cannot allow matter to be divisible to infinity: for let us 
suppose that the division has been carried out and then ask: 
what would ensue if the division was carried out? If each of the 
infinite number of parts has any magnitude, then it must be 
further divisible, which contradicts our hypothesis. If, on the 
other hand, the surviving parts have no magnitude, then they 
can never have amounted to any quantity: for zero multiplied by 
infinity is still zero. So we have to conclude that divisibility 
comes to an end, and the smallest possible fragments must be 
bodies with sizes and shapes. These tiny, indivisible bodies were 
called by Democritus ‘atoms’ (which is just the Greek word for 
‘indivisible’) (Aristotle, GC 1. 2. 316a13—b16).16
Atoms, Democritus believed, are too small to be detected by the 
senses; they are infinite in number and come in infinitely many 
varieties, and they have existed for ever. Against the Eleatics, he 
maintained 16tFhoar tA ritshtoetrl e’s  cwoaunst ern too thcios nartgruamdiecntti,o sne e Cinh . 5a dbemloiwtt.ing a 
vacuum: there was a void, and in this infinite empty space 
atoms were constantly in motion, just like motes in a sunbeam27. 
They come in different forms: they may differ in shape (as the 
letter A differs from the letter N), in order (as AN differs from 
NA), and in posture (as N
PYTHAGORAS TO PLATO
differs from Z). Some of them are concave and some convex, 
and some are like hooks and some are like eyes. In their 
ceaseless motion they bang into each other and join up with 
each other (KRS 583). The middle-sized objects of everyday life 
are complexes of atoms thus united by random collisions, 
differing in kind on the basis of the differences between their 
constituent atoms (Aristotle, Metaph. A 4. 985b4—20; KRS 556).
Like Anaxagoras, Democritus believed in plural worlds.
There are innumerable worlds, differing in size. In some worlds there is 
no sun and moon; in others there is a larger sun and a larger moon; in 
others there is more than one of each. The distances between one 
world and the next are various. In some parts of space there are more 
worlds, in others fewer; some worlds are growing, others shrinking; 
some are rising and some falling. They get destroyed when they collide 
with one another. There are some words devoid of animals or plants or 
moisture. (KRS 565)
For Democritus, atoms and the void are the only two realities: 
what we see as water or fire or plants or humans are only 
conglomerations of atoms in the void. The sensory qualities we 
see are unreal: they are due to convention.
Democritus explained in detail how perceived qualities arose 
from different kinds and configurations of atoms. Sharp flavours, 
for instance, originated from atoms that were small, fine, 
angular, and jagged, while sweet tastes were produced by 
larger, rounder, smoother atoms. The knowledge given us by the 
senses is mere darkness compared with the illumination that is 
given by the atomic theory. To justify these claims, Democritus 
developed a systematic epistemology.17
Democritus wrote on ethics as well as physics. Many aphorisms 
have been preserved, a number of which are, or have become, 
commonplace. But it is a mistake to think of him as a 
sententious purveyor of conventional wisdom. On the contrary, 
as will be shown in Chapter 8, a careful study of his remarks 
shows him to have beeTnh eon Seo pohf istthse first thinkers to have 
developed a systematic morality.
In the lifetime of Democritus, a younger compatriot from 
Abdera, Protagoras, was the doyen of a new class of 
philosopher: the sophists. Sophists
17 See Ch. 4 below.
28
PYTHAGORAS TO PLATO
were itinerant teachers who went from city to city offering 
expert instruction in various subjects. Since they charged fees 
for imparting their skills, they might be called the first 
professional philosophers if it were not for the fact that they 
offered instruction and services over a much wider area than 
philosophy even in the broadest sense. The most versatile, 
Hippias of Elis, claimed expertise in mathematics, astronomy, 
music, history, literature, and mythology, as well as practical 
skills as a tailor and shoemaker. Some other sophists were 
prepared to teach mathematics, history, and geography; and all 
sophists were skilled rhetoricians. They did brisk business in 
mid-fifth-century Athens, where young men who had to plead in 
law courts, or who wished to make their way in politics, were 
willing to pay substantial sums for their instruction and 
guidance.
The sophists made a systematic study of forensic debate and 
oratorical persuasion. In this pursuit they wrote on many topics. 
They started with basic grammar: Protagoras was the first to 
distinguish the genders of nouns and the tenses and moods of 
verbs (Aristotle, Rh. 3. 4. 1407b6—8). They went on to list 
techniques of argument, and tricks of advocacy. As interpreters 
of ambiguous texts, and assessors of rival orations, they were 
among the earliest literary critics. They also gave public lectures 
and performances, and set up eristic moots, partly for 
instruction and partly for entertainment (D.L. 9. 53). Altogether, 
their roles encompassed those in modern society of tutors, 
consultants, barristers, public relations professionals, and media 
personalities.
Protagoras first visited Athens as an ambassador for Abdera. He 
was held in honour by the Athenians and invited back several 
times. He was asked by Pericles to draw up a constitution for the 
new pan-Hellenic colony at Thurii in southern Italy in 444 bc. He 
gave his first public performance in Athens in the house of the 
tragedian Euripides. He read aloud a tract entitled On the Gods, 
whose opening words were long remembered: ‘About the gods, I 
cannot be sure whether they exist or not, or what they are like 
to see; for many things s18t aSened C hin.  4t bheelo w.ay of the knowledge of 
them, both the opacity of the subject and the shortness of 
human life’ (D.L. 9. 51). His most famous saying, ‘Man is t2h9e 
measure of all things’, encapsulated a relativist epistemology 
which will be examined in detail later in this book.18
PYTHAGORAS TO PLATO
Protagoras seems to have been prepared to argue on either 
side of any question, and he boasted that he could always make 
the worse argument the better. This may simply have meant 
that he could coach a weak client into the best presentation of 
his case; but by critics as different as Aristophanes and Aristotle 
he was taken to mean that he could make wrong seem right 
(Aristophanes, Clouds 112 ff, 656—7; Aristotle, Rh. 2. 24. 
1402a25). Protagoras’ enemies liked telling the story of the time 
when he sued his pupil Eualthus for non-payment of fees. 
Eualthus had refused to pay up, saying he had not yet won a 
single case. ‘Well,’ said Protagoras, ‘if I win this case, you must 
pay up because the verdict was given for me; if you win it, you 
must still pay up, because then you will have won a case’ (D.L. 
9. 56).
Another sophist, Prodicus from the island of Ceos in the 
Aegean, came to Athens, like Protagoras, on official business of 
his home state. He was a linguist, but more interested in 
semantics than grammar: he can perhaps be regarded as the 
first lexicographer. Aristophanes and Plato teased him as a 
pedant, who made quibbling distinctions between words that 
were virtually synonymous. In fact, however, some of the 
distinctions credited to him (such as that between two Greek 
equivalents of‘want’, boulesthai and epithumein; Plato, 
Protagoras 340b2) were later of serious philosophical 
importance.
Prodicus is credited with a romantic moral fable about the 
young Heracles choosing between two female impersonations of 
Virtue and Vice. He also had a theory of the origin of religion. 
‘The men of old regarded the sun and the moon, rivers and 
springs, and whatever else is helpful for life, as gods, because 
we are helped by them, just as the Egyptians worship the Nile’ 
(DK 84 B5). Thus, the worship of Hephaestus is really the 
worship of fire, and the worship of Demeter is really the worship 
of bread.
Gorgias, from Leontini in Sicily, once a pupil of Empedocles, 
was another sophist who came to Athens on an embassy, to 
seek help in a war against Syracuse. He was not only a 
persuasive orator, but a technician of rhetoric who categorized 
d30ifferent figures of speech, such as antithesis and rhetorical 
questions. His style was much admired in his own day, but was 
later regarded as excessively florid. Of his writings there have 
survived two short works of philosophical interest.
The first is a rhetorical exercise defending Helen of Troy 
against those who slander her, arguing that she deserves no 
blame for running off with
PYTHAGORAS TO PLATO
Paris and thus sparking off the Trojan war. ‘She did what she did 
either because of the whims of fortune, the decisions of the gods 
and the decrees of necessity, or because she was abducted by 
force, or persuaded by speech, or overwhelmed by love’ (DK 82 
B11, 21—4). Gorgias goes through these alternatives in turn, 
arguing in each case that Helen should be held free from blame. 
No human can resist fate, and it is the abductor, not the 
abductee, who merits blame. Thus far, Gorgias has an easy task: 
but in order to show that Helen should not be blamed if she 
succumbed to persuasion, he has to engage in an unconvincing, 
though no doubt congenial, encomium on the powers of the 
spoken word: ‘it is a mighty overlord, insubstantial and 
imperceptible, but it can achieve divine effects’. In this case, 
too, it is the persuader, not the persuadee, who should be 
blamed. Finally, if Helen fell in love, she is blameless: for love is 
either a god who cannot be resisted or a mental illness which 
should excite our pity. This brief and witty piece is the ancestor 
of many a philosophical discussion of freedom and determinism, 
force majeure, incitement, and irresistible impulse.
Gorgias’ work entitled On What is Not contained arguments for 
three sceptical conclusions: first, that there is nothing; secondly, 
that if there is anything it cannot be known; thirdly, that if 
anything can be known it cannot be communicated by one 
person to another. This suite of arguments has been handed 
down in two forms, once in the pseudoAristotelian treatise On 
Melissus, and once by Sextus Empiricus.
The first argument trades on the polymorphous nature of the 
Greek verb ‘to be’. I shall not spell out the argument here, but I 
shall endeavour in Chapter 6 to sort out the crucial ambiguities 
involved. The second argument goes like this. Things that have 
being can only be objects of thought if objects of thought are 
things that have being. But objects of thought are not things 
that have being; otherwise everything one thinks would be the 
case. But you can think of a man flying or of a chariot driven 
over the sea without there being any such things. Therefore, 
things that have being cannot be objects of thought. The third 
argument, the most plausible of the three, argues that each 
individual’s sensations are private and that all we can pass on to 
our neighbours is words and not experiences. 31
The arguments of this famous sophist for these distressing 
conclusions are indeed sophisms, and were no doubt dismissed 
as such by those who first encountered them. But it is easier to 
dismiss a sophism than to diagnose its nature, and it is harder to 
still to find its cure. The first
PYTHAGORAS TO PLATO
sophism was disarmed essentially by Plato in his dialogue 
appropriately named The Sophist.19 The second sophism 
involves a fallacious form of argument that sometimes occurs in 
Plato himself. Aristotle’s logic, however, made clear to 
subsequent thinkers that ‘Not all As are B’ does not entail ‘No B 
is an A’. The third argument, from the privacy of experience, was 
not given its definitive quietus until the work of Wittgenstein in 
the twentieth century.
Beside Protagoras, Hippias, Prodicus, and Gorgias there were 
other sophists whose names and reputations have come down to 
us. There was Callicles, for instance, the champion of the 
doctrine that might is right; and Thrasymachus, the debunker of 
justice as the self-interest of those in power. There were 
Euthydemus and Dionysidorus, a pair of logic choppers who 
would offer to prove to you that your father was a dog. These 
men, however, and even the better-known sophists whom we 
have considered, are known to us primarily as characters in 
Plato’s dialogues. Their philosophical contentions are best 
studied in the context of those dialogues. Searching for the 
historical truth about the sophists is no more rewarding than 
trying to discover what King Lear or Prince Hamlet were like 
before Shakespeare got hold of them.
We shall say goodbye, therefore, to these sophists and turn to 
consider Socrates, who, according to one view, was the greatest 
of the sophists, and according to another, was a paradigm of the 
true philosopher at the oppoSsoitcer aptoeles from any kind of sophistry.
In the history of philosophy Socrates has a place without 
parallel. On the one hand, he is revered as inaugurating the first 
great era of philosophy, and therefore, in a sense, philosophy 
itself. In textbooks all previous thinkers are lumped together in 
textbooks as ‘Presocratics’, as if philosophy prior to his age was 
somehow prehistoric. On the other hand, Socrates left behind no 
writing, and there is hardly a single sentence ascribed to him 
that we can be sure was his own utterance rather than a literary 
creation of one of his admirers. Our first-hand acquaintance with 
his philosophy is less 1® see Ch. 6 below.
32
PYTHAGORAS TO PLATO
than with that of Xenophanes, Parmenides, Empedocles, or 
Democritus. Yet his influence on subsequent philosophy, down 
to our own day, has been incomparably greater than theirs.
In antiquity many schools of thought claimed Socrates as a 
founder and many individuals revered him as a paragon 
philosopher. In the Middle Ages his history was not much 
studied, but his name appears on the page whenever a logician 
or metaphysician wishes to give an example: ‘Socrates’ was to 
scholastic philosophers what ‘John Doe’ long was to legal writers. 
In modern times Socrates’ life has been held up as a model by 
philosophers of many different kinds, especially by philosophers 
living under tyranny and risking persecution for refusal to 
conform to unreasoned ideology. Many thinkers have made their 
own the dictum that has as good a claim as any to be his own 
authentic utterance: ‘the unexamined life is not worth living’.
The hard facts of Socrates’ life do not take long to tell. He was 
born in Athens about 469 bc, ten years after the Persian 
invasions of Greece had been crushed at the battle of Plataea. 
He grew up during the years when Athens, a flourishing 
democracy under the statesman Pericles, exercised imperial 
hegemony over the Greek world. It was a golden age of art and 
literature, which saw the sculptures of Phidias and the building 
of the Parthenon, and in which Aeschylus, Sophocles, and 
Euripides produced their great tragedies. At the same time 
Herodotus, ‘the father of history’, wrote his accounts of the 
Persian Wars, and Anaxagoras introduced philosophy to Athens.
The second halfofSocrates’ life was overshadowed by the 
Peloponnesian War (431—4), in which Athens was eventually 
forced to cede the leadership of Greece to victorious Sparta. 
During the first years of the war he served in the heavy infantry, 
taking part in three major engagements. He acquired a 
reputation for conspicuous courage, shown particularly during 
the retreat after a disastrous defeat at Delium in 422. Back in 
Athens during the last years of the war, he held office in the 
city’s Assembly in 406. A group of commanders was tried for 
abandoning the bodies of the dead after a sea victory at 
Arginusae. It was unconstitutional to try the commanders 
collectively rather than individually, but Socrates was alone in 
voting against the illegality, and the accused were executed. 33
In 404, after the war had ended, the Spartans replaced Athenian 
democracy with an oligarchy, ‘the Thirty Tyrants’, long 
remembered for a reign
PYTHAGORAS TO PLATO
of terror. Instructed to arrest an innocent man, Leon of Salamis, 
Socrates took no notice. He refused to accept illegal orders, but 
seems to have taken no part in the revolution that overthrew the 
oligarchy and restored democracy. His uprightness had by now 
given both democrats and aristocrats a grievance against him, 
and the restored democrats remembered also that some of his 
close associates, such as Critias and Charmides, had been 
among the Thirty.
An aspiring democrat politician, Anytus, with two associates, 
caused an indictment to be drawn up against Socrates in the 
following terms: ‘Socrates has committed an offence by not 
recognizing the gods whom the state recognizes but introducing 
other new divinities. He has also committed the offence of 
corrupting the young. Penalty demanded: death’ (D.L. 2. 40). We 
have no record of the trial, though two of Socrates’ admirers 
have left us imaginative reconstructions of his speech for the 
defence. Whatever he actually said failed to move a sufficient 
number of the 500 citizen jurors. He was found guilty, albeit by a 
small majority, and condemned to death. After a delay in prison, 
due to a religious technicality, Socrates died in spring 399, 
accepting a poisonous cup of hemlock from the executioner.
The allegation of impiety in the indictment of Socrates was not 
something new. In 423 the dramatist Aristophanes had produced 
a comedy, The Clouds, in which he introduces a character called 
Socrates, who runs a college of chicanery which is also an 
institute of bogus research. Students at this establishment not 
only learn to make bad arguments trump good arguments, but 
also study astronomy in a spirit of irreverent scepticism about 
traditional religion. They invoke a new pantheon of elemental 
deities: air, ether, clouds, and chaos (260—6). The world, they 
are told, is governed not by Zeus, who does not exist, but by 
Dinos (literally ‘Vortex’), the rotation of the heavenly bodies 
(380—1). Much of the play is burlesque that is obviously not 
meant to be taken seriously: Socrates measures how many flea-
feet a flea can leap, and explores the clouds in a ramshackle 
flying machine. But the allegation that astronomy was 
incompatible with piety, if it was a joke, was a dangerous one. 
After all, it was only in the previous decade that Anaxagoras had 
b34een banished for asserting that the sun was a fiery lump. At the 
end of the play Socrates’ house is burnt down by an angry crowd 
of people who wish to punish him for insulting the gods and 
violating the privacy of the moon. To those who recalled
PYTHAGORAS TO PLATO
Aristophanes’ comedy, the events of 399 must have seemed a 
sorry case of life imitating art.
Some of Socrates’ traits in The Clouds are attributed to him also 
by other, more friendly writers. There is general agreement that 
he was pot-bellied and snub-nosed, pop-eyed and shambling in 
gait. He is regularly described as being shabby, wearing 
threadbare clothes, and liking to go barefoot. Even Aristophanes 
represents him as capable of great feats of endurance, and 
indifferent to privation: ‘never numb with cold, never hungry for 
breakfast, a spurner of wine and gluttony’ (414—17). From other 
sources it appears that he was a spurner of wine not in the 
sense of being a teetotaller, but as having an unusual ability to 
hold his liquor (Plato, Smp. 214a). Socrates married Xanthippe, 
with whom he had a son, Lamprocles; a stubborn, but perhaps 
ill-founded, tradition represents her as a shrew (D.L. 2. 36—7). 
According to some ancient writers he had two other sons by an 
official concubine, Myrto (D.L. 2. 26). In antiquity, however, he 
was best known for his attachment to the flamboyant aristocrat 
Alcibiades, some twenty years his junior: an attachment which, 
though passionate, remained, in the terminology of a later age, 
platonic. The Socrates of Xenophon
On more important issues, there is little that is certain about 
Socrates’ life and thought. For further information we are 
dependent above all on the two disciples whose works have 
come down to us intact, the soldierly historian Xenophon, and 
the idealist philosopher Plato. Both Xenophon and Plato 
composed, after the event, speeches for the defence at 
Socrates’ trial. Xenophon in addition wrote four books of 
memoirs of Socrates (memorabilia Socratis) and a Socratic 
dialogue, the Symposium. Plato, besides his Apology, wrote at 
least twenty-five dialogues, in all but one of which Socrates 
figures. Xenophon and Plato paint pictures of Socrates which 
differ from each other as much as the picture of Jesus given in 
the gospel of Mark differs from that in the gospel of John. While 
in Mark Jesus speaks in parables, brief aphorisms, and pointed 
responses to questions, the Jesus of the fourth gospel delivers 
extensive discourses that resonate at several levels. There is a 
similar contrast between Xenophon’s Socrates, who question3s5, 
argues, and exhorts in a workmanlike manner, and the Socrates 
of Plato’s Republic,
PYTHAGORAS TO PLATO
who delivers profound metaphysical lectures in a style of layered 
literary artifice. Just as it was John’s presentation of Jesus that 
had the greatest impact on later theological development, so it 
is the Socrates ofPlato whose ideas proved fertile in the history 
of philosophy.
According to Xenophon, Socrates was a pious man, punctiliously 
observant of ritual and respectful of oracles. In his prayers he let 
the gods decide what was good for him, since the gods were 
omnipresent and omniscient, knowing everyone’s words, 
actions, and unspoken intentions (Mem. 1. 2. 20; 3. 2). He taught 
that the poor man’s mite was as pleasing to the gods as the 
grand sacrifices of the rich (Mem. 1. 3. 3). He was a decent, 
temperate person, devoid of avarice and ambition, moderate in 
his desires, and tolerant of hardship. He was not an educator, 
though he taught virtue by practice as well as exhortation, and 
he discouraged vice by teasing and fable as well as by reproof. 
He was not to be blamed if some of his pupils went to the bad in 
spite of his example. Though critical of some aspects of Athenian 
democracy, he was a friend of the people, and totally innocent of 
crime and treason (Mem. 1. 2).
Xenophon’s major concern in his memoirs was to exonerate 
Socrates from the charges made against him at his trial, and to 
show that his life was such that conservative Athenians should 
have revered him rather than condemned him to death. 
Xenophon is also anxious to place a distance between Socrates 
and the other philosophers of the age: unlike Anaxagoras he had 
no futile interest in physics or astronomy (Mem. 1.1. 16), and 
unlike the sophists he did not charge any fees or pretend to 
expertise that he lacked (Mem. 1. 6—7).
Xenophon's Socrates is an upright, rather wooden person, 
capable of giving shrewd, commonsensical advice in practical 
and ethical matters. In discussion he is quick to resolve 
ambiguities and to deflate cant, but he rarely ventures upon 
philosophical argument or speculation. In a rare case when he 
does so it is, significantly, in order to prove the existence and 
providence of God. If an object is useful, Socrates argues, it must 
be the product of design, not chance; but our sense-organs are 
eminently useful and delicately constructed. ‘Because our sight 
i3s6 delicate, it has been shuttered with eyelids which open when 
we need to use it, and close in sleep; so that not even the wind 
will damage it, eyelashes have been planted as a screen; and 
our foreheads have been fringed with eyebrows to prevent harm 
from the head’s own sweat’ (Mem. 1. 4. 6). Such contrivances, 
and the
PYTHAGORAS TO PLATO
implantation of the instincts for procreation and self-
preservation, look like the actions of a wise and benevolent 
craftsman (demiourgos). It is arrogant to think that we humans 
are the only location of Mind (nous) in the universe. It is true 
that we cannot see the cosmic intelligence that governs the 
infinite multitudinous universe, but we cannot see the souls that 
control our own bodies either. Moreover, it is absurd to think 
that the cosmic powers that be have no concern for humans: 
they have favoured humans above all other animals by 
endowing them with erect posture, multi-purpose hands, 
articulate language, and all-year-round sex (Mem. 1. 4. 11-12).
Despite this anticipation of the perennial Argument from Design, 
there is little in Xenophon’s work that would entitle Socrates to a 
prominent position in the history of philosophy. Several of the 
Presocratics would be more than a match for Xenophon’s 
Socrates in scope, insight, and originality. The Socrates who has 
captured the imagination of succeeding generations of 
philosophers is the Socrates of Plato, and it is he with whom we 
shall henceforth be concerned.
The Socrates of Plato
It is, however, an oversimplification to speak of a Platonic 
Socrates, because Plato’s dialogues do not assign a consistent 
role or personality to the character called Socrates. In some 
dialogues he is predominantly a critical inquirer, challenging the 
pretensions of other characters by a characteristic technique of 
question and answer—elenchus—which reduces them to 
incoherence. In other dialogues Socrates is quite willing to 
harangue his audience, and to present an ethical and 
metaphysical system in dogmatic form. In yet other dialogues 
he plays only a minor part, leaving the philosophical initiative to 
a different protagonist. Before going further, therefore, we must 
digress to consider when and where the dialogues can be taken 
to be presenting Socrates’ actual views, and when and where 
the character Socrates is acting as a mouthpiece for Plato’s own 
philosophy.
In recent centuries scholars have sought to explain these 
differences in chronological terms: the different role assigned to 
Socrates in different dialogues represents the development 3o7f 
Plato’s thought and his gradual
PYTHAGORAS TO PLATO
Socrates and Plato as portrayed by Matthew Paris in the thirteenth 
century. Who is teaching whom?
emancipation from the teaching of his master. The initial clue to 
a chronological ordering of the dialogues was given by Aristotle, 
who tells us that Plato’s Laws was written later than the 
Republic (Pol. 2. 6. 1264b24—7).
38
PYTHAGORAS TO PLATO
There is indeed a tradition that the Laws was unfinished at 
Plato’s death (D.L. 3. 37). On this basis nineteenth-century 
scholars sought to establish a grouping of the dialogues, 
beginning from the final stage of Plato’s life. They studied the 
frequency in different dialogues of different features of style, 
such as the use of technical terms, preferences between 
synonymous idioms, the avoidance of hiatus, and the adoption 
of particular speech rhythms.
On the basis of these stylometric studies, which by the end of 
the nineteenth century had covered some 500 different 
linguistic criteria, a consensus emerged that a group of 
dialogues stood out by its similarity to the Laws. All scholars 
agreed on including in the group the dialogues Critias, Philebus, 
Sophist, Statesman, and Timaeus, and all agreed that the group 
represented the latest stage of Plato’s writing career. There was 
no similar consensus about ordering within the group: but it is 
notable that the group includes all the dialogues in which 
Socrates’ role is at a minimum. Only in the Philebus is he a 
prominent character. In Laws he does not appear at all, and in 
the Timaeus, Critias, Sophist, and Politicus he has only a walk-on 
part while the lead role is given to another: in the first two to the 
protagonist named in the dialogue’s title, and in the latter two to 
a stranger from Parmenides’ town of Elea. It seemed reasonable, 
therefore, to regard the dialogues of this group as expressing 
the views of the mature Plato rather than those of his long-dead 
teacher.
In dividing the earlier dialogues into groups, scholars could once 
again follow a clue given by Aristotle. In Metaph. M 4. 1078b27—
32 he sets out the prehistory of Plato’s Theory of Ideas, and 
assigns the following role to Socrates: ‘Two things may fairly be 
attributed to Socrates: inductive arguments and general 
definitions; both are starting points of scientific knowledge. But 
he did not regard the universal or the definitions as separate 
entities, but [the Platonists] did, and called them Ideas of 
things.’ Expositions of the Theory of Ideas are placed in the 
mouth of Socrates in several important dialogues, notably 
Phaedo, Republic, and Symposium. In these dialogues Socrates 
appears not as an inquiring questioner, but as a teacher in full 
possession of a system of philosophy. By stylometric criter3i9a 
these dialogues are closer than other dialogues to the late group 
already described. It is reasonable, therefore, to treat them as a 
middle group in the corpus, and to regard them as representing 
Plato’s own philosophy rather than Socrates’.
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A third group of dialogues can be identified by a set of 
common features: (1) they are short; (2) Socrates appears as an 
inquirer, not an instructor; (3) the Theory of Ideas is not 
presented; and (4) stylometrically they are at the greatest 
remove from the late group first identified. This group includes 
Crito, Charmides, Laches, Lysis, Ion, Euthydemus, and Hippias 
Minor. These dialogues are commonly accepted as those most 
likely to be presentations of the philosophical views of the 
historical Socrates. Here too belongs the Apology, in which 
Socrates is the sole speaker, on trial for his life, and which in 
philosophical content and stylometric features resembles the 
other dialogues of the group. The first book of the Republic, too, 
in both content and style, resembles this group more than it 
resembles the remaining books of the dialogue: some scholars 
suppose, with good reason, that it first existed as a separate 
dialogue, perhaps under the title Thrasymachus. It is difficult to 
assign a chronology within this early group, though some 
authors place the Lysis first and assign it before 399, on the 
basis of an ancient anecdote that it was read to Socrates 
himself, who said, ‘what a load of lies this young man tells about 
me’ (D.L. 3. 35).
In my view there is good reason to accept the general 
consensus that thus divides the Platonic dialogues into three 
groups, early, middle, and late. The division results from the 
striking coincidence of three independent sets of criteria, 
dramatic, philosophical, and stylometric. Whether we focus on 
the dramatic role given to Socrates, or the philosophical content 
of the dialogues, or tell-tale details of style and idiom, we reach 
the same threefold grouping. Twentieth-century developments 
in stylometry, with much more refined statistical techniques, and 
with vast amounts of new data obtained from computerised 
texts, have essentially done little more than confirm the 
consensus achieved in the late nineteenth and early twentieth 
century.20 21
A nu20m   b Tehre o cfo dnisaelnosguuse hsa, sh boeweenv seigrn, idfioc annotlty  fqaulle cslteioanrelyd  ionntloy  oinn e of 
the rtehsrpeeec tg orfo tuhpes T, imbeaecuasu asned  tihtse a pthpreened ixc,r ittheer iCar itdiaos . nTohte  dsoeb hataep pily 
he2r1e    w Silele b Le.  eBxraamndinweodo lda,t eTrh ew Chherno nIo dloisgcyu osfs P Plaltaot’os ’Ds iaTlhoegouerys ofIdeas.
coinc(Cidaem: britdhgee : Cmamosbtr idgime Uponirvtearnsti ty sPurecshs , 1c9a9s0e);s  G. aLreed geCr,r aRtey- lus, 
Euthcyopuhntrion,g  PGlaotorg: Aia Cso, mMpuetnero A, nPalhysaies dofr uPlsa,t o’Psa Srtmylee n(Oidxefosr,d :P Crolatraegnodroans , 
TheaPerteests, 40 us
1.9 8H9e)r;e more recent stylometric studies have thrown 
new light on the problems.21 There is no space here to enter into 
the detailed
PYTHAGORAS TO PLATO
arguments for assigning each of these dialogues to a particular 
period, so I will simply state the chronology that appears to me 
most probable after an examination of the three sets of criteria.
Gorgias, Protagoras, and Meno seem to belong between the first 
and second group. Though the Theory of Ideas is absent from 
the discussion, the role of Socrates is closer to the didactic 
philosopher of the middle dialogues than to the agnostic inquirer 
of the early dialogues. The order suggested by philosophical 
considerations is Protagoras, Gorgias, Meno; the order that 
emerges from stylometric studies is Meno, Protagoras, Gorgias. 
The Cratylus in style is close to these three, but is difficult to 
place precisely. The Euthyphro is generally considered an early 
dialogue, but it contains a hint of the Theory of Ideas, and 
stylistic indicators place it close to the Gorgias. Accordingly, I 
would place it in this intermediate group.
The Phaedrus was sometimes thought in antiquity to be the 
earliest of Plato’s dialogues (D.L. 3. 38), but on both doctrinal 
and stylistic grounds the dialogue fits reasonably well into the 
middle group. The case is not the same with two other very 
important dialogues that in style are close to the Phaedrus, 
namely the Parmenides and Theaetetus. In content these works 
stand at some distance from the classical Theory of Ideas, which 
is ignored in the Theaetetus and subjected to severe criticism in 
the Parmenides. In structure the Parmenides differs from all 
other dialogues; the Theaetetus resembles the dialogues of the 
early group. Internal references in the Theaetetus look 
backwards to the Parmenides (183e) and forwards to the Sophist 
(210d). On balance it seems sensible to place these two 
dialogues between the middle and the later dialogues, but a 
discussion of the pSroobcrleamtess ’ iOn wgniv Pinhgilo aso pcohhyerent statement of 
Plato’s philosophical position at this period will have to wait until 
wIt ew haasv en geicveesns arny  atcoc oeusntta obfli sthe  aT hpeloaruys iobfl eId ecahsr.onology for the 
Platonic texts in order to indicate to what extent it is safe to rely 
on Plato as a source of information about the historical Socrates. 
Having done this, we can give an
J. T. Temple, ‘A Multivariate Synthesis of Published Platonic 
Stylometric Data’, Literary and Linguistic Computing, 11/2 (1996), 67—75.
41
PYTHAGORAS TO PLATO
account of Socrates’ own philosophy as it is presented in the 
early dialogues of his pupil. In the Apology Plato is anxious, like 
Xenophon, to defend Socrates from the charge of atheism. He 
points to the inconsistency between the two charges, that he is 
an atheist and that he introduces strange divinities. He also 
distances him from the secular physicism of Anaxagoras. The 
denial in the Apology that he had ever discussed physics (19d) 
does not ring altogether true, even though it is echoed later by 
Aristotle (Metaph. A 6. 987b2). If Socrates had never shown any 
interest in issues of cosmology, Aristophanes’ mockery would 
have been so wide of the mark that the jokes would have fallen 
very flat. Moreover, Plato himself in his Phaedo represents 
Socrates as confessing that he at one time shared Anaxagoras’ 
curiosity about whether the earth was flat or round and whether 
it was in the middle of the universe, and what was the reason for 
the motion and speed of the sun and moon and other heavenly 
bodies (Phd. 97b—99a).
It may have been Socrates’ disillusionment with Anaxagoras 
that made him give up scientific inquiry and concentrate on the 
issues which, according to the Apology and Aristotle, dominated 
the latter part of his life. According to both Plato and Xenophon, 
another factor that directed his interest was an oracle uttered in 
the name ofApollo by the entranced priestess in the shrine at 
Delphi. When asked if there was anyone in Athens wiser than 
Socrates, the priestess replied in the negative. Socrates 
professed to be puzzled by this response, and began to question 
different classes of people who claimed to possess wisdom of 
various kinds. It soon became clear that politicians and poets 
possessed no genuine expertise at all, and that craftsmen who 
were genuine experts in a particular area would pretend to a 
universal wisdom to which they had no claim. Socrates 
concluded that the oracle was correct in that he alone realized 
that his own wisdom was worthless (23b).
It was in matters of morality that it was most important to 
pursue genuine knowledge and to expose false pretensions. For 
according to Socrates virtue and moral knowledge were the 
samFeor t ah ifnuglle: rn doi socnuses iwonh oo fr tehaisll yre kmnaerwka bwlhe adto cwtraisn et,h ‘eth be eSsotc rtahtiincg P atora dox’, see Ch. 8 below.
do could do otherwise, and all wrongdoing was the result of 
i4g2norance.22 This makes it all the more absurd that he should be 
accused of corrupting the young. Anyone would obviously prefer 
to live among good men than among bad men, who might harm 
him. He cannot, therefore, have any motive for corrupting
PYTHAGORAS TO PLATO
the young on purpose; and if he is doing so unwittingly he 
should be educated rather than prosecuted (26a).
Socrates, in the Apology, did not claim to possess himself the 
wisdom that is sufficient to keep a man from wrongdoing. 
Instead, he said that he relied on an inner divine voice, which 
would intervene if ever he was on the point of taking a wrong 
step (41d). So far from being an atheist, his whole life was 
dedicated to a divine mission, the campaign to expose false 
wisdom which was prompted by the Delphic oracle. What would 
really be a betrayal of God would be to desert his post through 
fear of death. If he were told that he could go free on condition 
that he abandon philosophical inquiry, he would reply, ‘Men of 
Athens, I honour and love you; but I shall obey God rather than 
you, and while I have life and strength I shall never cease from 
the practice and teaching of philosophy’ (29d).
The early dialogues of Plato portray Socrates carrying out his 
philosophical mission. Typically, the dialogue will be named after 
a personage who claims knowledge of a certain subject or who 
can be taken to represent a certain virtue: thus the Ion, on 
poetry, is named after a prizewinning rhapsode (a reciter of 
Homer), and the Laches, on courage, is named after a 
distinguished general. Charmides and Lysis, on passion, 
temperance, and friendship, are named after two bright young 
men who commanded a circle of aristocratic admirers. In each 
dialogue Socrates seeks a scientific account or definition of the 
topic under discussion, and by questioning reveals that the 
eponymous protagonist is unable to give one. The dialogues all 
end with the ostensible failure of the inquiry, confirming the 
conclusion in the Apology that those who might most be 
expected to possess wisdom on particular topics fail, under 
examination, to exhibit it.
The search for definitions serves different purposes in different 
dialogues: a definition of justice is sought in Republic 1 in order 
to determine whether justice benefits its possessor, and a 
definition of piety is sought in the Euthyphro in order to settle a 
particular difficult case of conscience. But Aristotle was right to 
pick out the search as a notable feature of Socratic method. The 
method has sometimes been criticized as involving the fallacious 
claim that we cannot ever know whether some particular acti4o3n 
is or is not, say, just or pious unless we can give a watertight 
definition of justice and piety. Such a claim would be 
inconsistent with Socrates’ regular practice in the course of his 
elenchus of seeking agreement whether particular actions (such 
as returning a borrowed knife to
PYTHAGORAS TO PLATO
a madman, or carrying out a strategic retreat in battle) do or do 
not exhibit particular virtues such as justice and courage. 
Socrates’ method involves only the weaker claim that unless we 
have a general definition of a virtue we will not (a) be able to say 
whether the virtue universally has a particular property, such as 
being teachable, or being beneficial, or (b) be able to decide 
difficult borderline cases, such as whether a son’s prosecuting 
his father for the manslaughter of an accused murderer is or is 
not an act of piety.
The other feature of Socrates’ method emphasized by Aristotle, 
namely the use of inductive arguments, does in fact presuppose 
that we can be sure of truths about individual cases while still 
lacking universal definitions. Plato’s Socrates does not claim to 
have a watertight definition of techne, or craft; but over and 
over again he considers particular crafts in order to extract 
general truths about the nature of a craft. Thus, in Republic 1 he 
wishes to show that the test of a good craftsman is not whether 
he makes a lot of money, but whether he benefits the objects of 
his craft. To show this he runs through the products of different 
crafts: a good doctor produces healthy patients, a good captain 
delivers safe navigation, a good builder constructs a good house, 
and so on. How much money these people make is not relevant 
to their goodness at their craft; it tells us only how efficient they 
are at the quite different craft of moneymaking (Rep. 1. 346a—
e).
The two procedures identified by Aristotle are, in Socrates’ 
method, closely related to each other. The inductive argument 
from particular instances to general truths is a contribution to 
the universal definition, even though the contribution in these 
dialogues is forever incomplete, never leading to an exception-
proof definition. In the absence of the universal definition of a 
virtue, the general truths are applied to help settle difficult 
borderline cases of practice, and to evaluate preliminary 
hypotheses about the virtue’s properties. Thus, in the Republic 
case, the induction is used to show that a good ruler is one who 
benefits his subjects, and therefore justice is not (as one of the 
characters in the dialogue maintains) simply whatever is to the 
advantage of those in power.
I4n4 these early dialogues about the virtues, in spite of Socrates’ 
profession of ignorance, a number of theses emerge both about 
knowledge and about virtue. These will be explored in greater 
detail in later chapters on epistemology and ethics. For the 
moment we may notice that the issues
PYTHAGORAS TO PLATO
converge on the question: Can virtue be taught? For if virtue is 
knowledge, then surely it must be teachable; and yet it is 
difficult to point to any successful teachers of virtue.
In Athens, however, there was no lack of people claiming to have 
the relevant expertise, namely the sophists. At the end of the 
early period, and before the central period of Plato’s writing 
career, we find a series of dialogues named after major sophists
—Hippias, Gorgias, Protagoras— which address the question 
whether virtue can be taught and which deflate the pretensions 
of the sophists to possess the secret of its teachability. The 
Hippias Minor sets out a serious difficulty for the idea that virtue 
is a craft that can be learnt. A craftsman who makes a mistake 
unknowingly is inferior to a craftsman who makes a mistake 
deliberately; so if virtue is a craft, one who sins deliberately is 
more virtuous than one who sins in ignorance (376b). The 
Gorgias argues that rhetoric, the main arrow in the sophist’s 
quiver, is incapable of producing genuine virtue. The Protagoras 
seems to suggest—whether seriously or ironically—that virtue is 
indeed teachable, because it is the art of calculating the 
proportion of pleasure and pain among the consequences of 
one’s actions.23 From Socrates to Plato
Whether or not this is Socrates’ last word on the teachability of 
virtue, a reader of the dialogues soon finds a quite different 
answer being given, in the Meno and the Phaedo. Virtue, and 
the knowledge of good and evil, which according to Socrates is 
identical with virtue, cannot be taught in the present life: it can 
only be recovered by recollection of another and better world. 
This is presented not as a particular thesis about virtue, but as a 
general thesis about knowledge. In the Meno it is claimed that a 
slave-boy who has never been taught geometry can be brought, 
by suitable questioning, to recall significant geometrical truths 
(82b—86a). In the Phaedo it is argued that though we often see 
things that are more or less equal in size, we never see a pair of 
things absolutely equal to each other. The idea of absolute 
equality cannot therefore be derived from experience, but must 
have been acquired in a2 3p rSeevei oCuhs.  8li fbee. loTwhe.  same
45
PYTHAGORAS TO PLATO
goes for similar ideas such as that of absolute goodness and 
absolute beauty (74b—75b).
The Meno and the Phaedo therefore introduce two doctrines—
the Theory of Ideas, and the thesis of recollection—which by the 
common consent of scholars belong to Plato, and not to the 
historical Socrates. They effect the ‘separation’, of which 
Aristotle spoke, between the universal definitions sought by 
Socrates and the empirical entities of our everyday world.
The Phaedo also contains Plato’s account of the last days of 
Socrates in prison. Socrates’ friend Crito has (in the dialogue 
named after him) failed to gain acceptance of a plan for escape. 
Socrates has rejected the proposal, saying that he owes so much 
to the laws of Athens, under which he was born and bred and 
lived contentedly, that he cannot now turn his back on his 
covenant with them and run away (51d—54c). The arrival of a 
ship from the sacred isle of Delos marks the end of the religious 
stay of execution, and Socrates prepares for death by engaging 
his friends in a long discussion of the immortality of the soul.24 
The discussion ends with Socrates’ narrating a series of myths 
about the journeys in the underworld of the soul after it survives 
death.
Crito asks whether Socrates has any instructions about his 
burial; he is told to remember that he will be burying only the 
body, and not the soul, which is to go to the joys of the blessed. 
After his last bath Socrates says farewell to his family, jokes with 
his gaoler, and accepts the cup of hemlock. He is represented 
(with a degree of medical improbability) as composing himself 
serenely as sensation gradually deserts his limbs. His last words, 
like so many in his life, are puzzling: ‘Crito, I owe a cock to 
Aesculapius [the god of healing]. Please remember to pay the 
debt.’ Once again we ask ourselves whether he means his words 
literally or is employing his unique form of irony.
It is perhaps no coincidence that it is in one and the same 
dialogue that Plato records the last hours of Socrates and 
introduces clearly for the first time his own characteristic Theory 
of Ideas. As well as the physical death of Socrates, we witness 
the de2m4 Tishe pohfil ohsoisp hipcearl sconatel ntp ohfi ltohsiso pdhisyc,u sstoio nb ise  anrealiynsceadr nbaetloewd in Ch. 7.
henceforth in the more metaphysical and mythical form 
o46fPlatonism.
When Socrates died, Plato was in his late twenties, having been 
his pupil for about eight years. A member of an aristocratic 
Athenian family, Plato
A herm of Socrates, bearing a quotation from Plato’s Onto
PYTHAGORAS TO PLATO
would have been just old enough to have fought in the 
Peloponnesian War, as his brothers Glaucon and Adeimantus 
certainly did. His uncles Critias and Charmides were two of the 
Thirty Tyrants, but he himself took no part in Athenian political 
life. At the age of 40 he went to Sicily and became an associate 
of Dion, the brother-in-law of the reigning monarch, Dionysius I; 
during this visit he made the acquaintance of the Pythagorean 
philosopher Archytas. On his return to Athens he founded a 
philosophical community, the Academy, in a private grove 
beside his own house. Here a group of thinkers, under his 
direction, shared with each other their interests in mathematics, 
astronomy, metaphysics, ethics, and mysticism. When 60 years 
old he was invited back to Sicily by Dion’s nephew, who had now 
succeeded to the throne as Dionysius II; but his visit was not a 
success because Dion and Dionysius quarrelled with each other. 
A third visit as a royal adviser was equally abortive, and Plato 
returned home disillusioned in 360. He died peacefully at a 
wedding feast in Athens, himself unmarried, in the year 347, 
being aged about 80.
Writers in antiquity wove many stories around Plato’s life, few of 
which deserve credence. If we wish to put flesh around the bare 
bones of his biography, we do best to read the Letters that have 
traditionally been included in his works. Though some, if not all, 
are the composition of other authors, they contain information 
that is much more plausible than the anecdotes to be found in 
the Life of Plato by Diogenes Laertius. They profess to be from 
the last two decades of Plato’s life and principally concern his 
involvement in the government ofSyracuse and his attempt to 
convert a tyranny into a constitution embodying his own political 
ideals.
Plato’s works as handed down to us amount to some half a 
million words. Though probably some of the works in the corpus 
are spurious, there are no written works attributed to Plato in 
antiquity that have not survived today. However, later writers in 
antiquity, in addition to making copious citations of his 
dialogues, from time to time attach importance to an oral 
tradition of his lectures in the Academy.
Because Plato chose to write in dialogue form, and never himself 
a48ppears in them as a speaker, it is difficult to be sure which of 
the varied philosophical theses expounded by his characters 
were ones to which he was himself committed. We have seen 
this par excellence in the case of his Socrates, but similar 
caution must be exercised in attributing to him the doctrines of 
the other main interlocutors in the dialogues,
PYTHAGORAS TO PLATO
Timaeus, the Eleatic Stranger in the Sophist and Statesman, and 
the Athenian Stranger in the Laws. The dialogue form enabled 
Plato to suspend judgement about difficult philosophical issues, 
while presenting the strongest arguments he could think of on 
both sides of the question (cf. D.L. 3. 52).
The Theory of Ideas
The best known of the doctrines to be found in Plato’s dialogues 
is the Theory of Ideas. In the central dialogues, from the 
Euthyphro onwards, the theory is more often alluded to, taken 
for granted, or argued from, than explicitly stated and formally 
established. The clearest short statement of the theory is found 
not in the dialogues but in the seventh of the Letters 
traditionally attributed to Plato, which is largely devoted to a 
defence of his activities in Sicily. The authenticity of this letter 
has often been rejected in modern times. There is, however, no 
better ground for rejecting Plato’s Seventh Epistle to the 
Syracusans than there is for rejecting Paul’s Second Epistle to 
the Corinthians (which it resembles in several ways). Certainly 
there is no good stylometric reason for calling it into question.25 
If it is not authentic, then it is one of the clearest and most 
authoritative statements of the theory to be found in all the 
secondary literature on Plato. Hence it provides a useful starting 
point for the exposition of the theory.
The letter states the following as a fundamental doctrine that 
Plato has often expounded:
For each thing that there is three things are necessary if we are to 
come by knowledge: first, the name, secondly, the definition, and 
thirdly, the image. Knowledge itself is a fourth thing, and there is a fifth 
thing that we have to postulate, which is that which is knowable and 
truly real. To understand this, consider the following example and 
regard it as typical of everything. There is something called a circle; it 
has a name, which we have just this minute used. Then there is its 
definition, a compound of nouns and verbs. We might give ‘The figure 
whose limit is at every point equidistant from its centre’ as the 
definiti2o5n  Loefd gwehra, tReev-ecro uinst irnogu Pnladt,o ,c 1ir4c8u—la5r,0 ,o 2r 2a4 , criercglaer. dTsh tihrdel yS,e vthenerteh  is 
whatL wetet edrr aaws ,a ourt hreunbt iocu, ta, nodr  crolotsaete i,n o tri mcaen tcoe tl.h Teh Peh icleirbcules,  itthsee lffi rwsht ich all 
dialogue of the final period.
these symbolize
49
PYTHAGORAS TO PLATO
does not undergo any such change and is a quite different thing. In the 
fourth place we have knowledge, understanding, and true opinion on 
these matters— these, collectively, are in our minds and not in sounds 
or bodily shapes, and thus are clearly distinct from the circle itself and 
from the three entities already mentioned. Of all these items, it is 
understanding that is closest to the fifth in kinship and likeness; the 
others are at a greater distance. What is true of round is also true of 
straight, of colour, of good and beautiful, and just; of natural and 
manufactured bodies; of fire, water, and the other elements; of all 
living beings and moral characters; of all that we do and undergo. In 
each case, anyone who totally fails to grasp the first four things will 
never fully possess knowledge of the fifth. (342a—d)
If I follow Plato, then, I will begin by distinguishing four things: 
the word ‘circle’, the definition of circle (a series of words), a 
diagram of a circle, and my concept of a circle. The importance 
of being clear about these four items is to distinguish them 
from, and contrast them with, a fifth thing, the most important 
of all, which he calls ‘the circle itself. It is this that is one of the 
Ideas of which Plato's celebrated theory treats. The theory is a 
wide-ranging one, as is clear from the sentence at the end of the 
paragraph that lists the Welds in which the theory applies. In his 
other writings Plato uses many other expressions to refer to 
Ideas. ‘Forms’ (eide) is probably the most common, but the Idea 
or Form of X may be called ‘the X itself’, ‘that very thing that is 
X’, or ‘Xness’, or ‘what X is’.
It is important to note what is absent from Plato's list in the 
Seventh Letter. He does not mention, even at the lowest level, 
actual material circular objects such as cartwheels and barrels. 
The reason for his omission is clear from other passages in his 
writings (e.g. Phd. 74a—c). The wheels and barrel we meet in 
experience are never perfectly circular: somewhere or other 
there will be a bend or bump which will interfere with the 
equidistance from the centre of every point on the 
circumference. This is true too, for that matter, of any diagram 
we may draw on paper or in the sand. Plato does not stress this 
point here, but it is the reason why he says that the diagram is 
at a greater distance from the circle itself than my concept is. 
My subjective concept of the circle—my understanding of what 
‘circle’ means—is not the same as the Idea of the circle, because 
t5h0e Idea is an objective reality that is not the property of any 
individual mind. But at least the concept in my mind is a 
concept of a perfect circle; it is not merely an imperfect 
approximation to a circle, as the ring on my finger is.
PYTHAGORAS TO PLATO
In the passage I have cited, Plato arrives at the Idea of circle 
after starting from a consideration of the word ‘circle’ as it 
occurs in the subject-place of a sentence such as
A circle is a plane figure whose circumference is everywhere 
equidistant from its centre.
However, he sometimes introduces the Idea of X by reflection 
on sentences in which ‘X’ appears not in subject-place, but as a 
predicate.
Consider the following. Socrates, Simmias, and Cebes are all 
called ‘men’; they have it in common that they are all men. Now 
when we say ‘Simmias is a man’ we may wonder whether the 
word ‘man’ names or stands for something in the way that the 
name ‘Simmias’ stands for the individual man Simmias? If so, 
what? Is it the same thing as the word ‘man’ stands for in ‘Cebes 
is a man’? In order to deal with questions of this kind, Plato 
introduces the Idea of Man. It is that which makes Simmias, 
Cebes, and Socrates all men; it is the prime bearer of the name 
‘Man’.
In many cases where we would say that a common predicate 
was true of a number of individuals, Plato will say that they are 
all related to a certain Idea or Form: where A, B, C, are all F, they 
are related to a single Form of F. Sometimes he will describe this 
relation as one of imitation: A, B, C, all resemble F. Sometimes 
he will talk rather of participation: A, B, C all share in F, they 
have F in common between them. It is not clear how universally 
we are to apply the principle that behind common predication 
there lies a common Idea. Sometimes Plato states it universally, 
sometimes he hesitates about applying it to certain particular 
sorts of predicate. Certainly he lists Ideas of many different 
types, such as the Idea of Good, the Idea of Bed, the Idea of 
Circle, the Idea of Being. He is prepared to extend the theory 
beyond single-place predicates such as ‘is round’ to two-place 
predicates like ‘is distinct from’. When we say that A is distinct 
from B and when we say that B is distinct from A, although we 
use the word ‘distinct’ twice, each time we are applying it to a 
single entity.
We may state a number of Platonic theses about Ideas and 
their relations to ordinary things in the world.
(1) The Principle of Commonality. Wherever several things a5r1e 
F, this is because they participate in or imitate a single Idea of F 
(Phd. 100c; Men. 72c, 75a; Rep. 5. 476a10, 597c).
PYTHAGORAS TO PLATO
(2)    The Principle of Separation. The Idea of F is distinct from 
all the things that are F (Phd. 74c; Smp. 211b).
(3) The Principle of Self-Predication. The Idea of F is itself F 
(Hp. Ma. 292e; Prt. 230c—e; Prm. 132a—b).
(4) The Principle of Purity. The Idea of F is nothing but F (Phd. 
74c; Smp. 211e).
(5)    The Principle of Uniqueness. Nothing but the Idea of F is 
really, truly, altogether F (Phd. 74d, Rep. 5. 479a—d).
(6)    The Principle of Sublimity. Ideas are everlasting, they 
have no parts and undergo no change, and they are not 
perceptible to the senses (Phd. 78d; Smp. 211b).
The Principle of Commonality is not, by itself, uniquely 
Platonic. Many people who are unhappy with talk 
of‘participation’ are content to speak of attributes as being 
‘in common’ among many things which have them. They 
may say, for instance, ‘If A, B, and C are all red, then this 
is because they have the property of being red in 
common, and we learn the meaning of‘red’ by seeing what 
is common among the red things.’ What is peculiar to 
Plato is that he seriously follows up what is implied if one 
uses the metaphor of ‘having in common’.26 For instance, 
there must be only a single Idea of F, otherwise we could 
not explain why the F things have something in common 
(Rep. 597b—c).
The Principle of Separation is linked with the notion of a 
hierarchy between Ideas and the individuals that 
exemplify them. To participate and to be participated in 
are two quite different relationships, and the two terms of 
these relationships must be on a different level.
The Principle of Self-Predication is important for Plato, 
because without it he could not show how the Ideas 
explain the occurrence of properties in individuals. Only 
what is hot will make something hot; and it is no good 
drying yourself with a wet towel. So, in general, only what 
is itself F can explain how something else is F. So if the 
Idea of Cold is to explain why snow is cold, it must itself be 
cold (Phd. 103b—e).
The Idea of F is not only F, it is a perfect specimen of an F. It 
52 cannot be diluted or adulterated by any element other 
than Fness: hence the Principle of Purity. If it were to 
possess any property other than being F, it would have to 
do so by participating in some other Idea, which would
26 I owe this point to G. E. M. Anscombe, Three Philosophers (Oxford: 
Blackwell, 1961), 28.
PYTHAGORAS TO PLATO
surely have to be superior to it in the way that the Idea of F is 
superior to all the non-ideal Fs. The notion of stratified 
relationships between Ideas opens up a Pandora’s box which 
Plato, when presenting the classical Theory of Ideas in his 
central dialogues, preferred to keep closed.
The Principle of Uniqueness is sometimes stated in a misleading 
way by commentators. Plato frequently says that only Ideas 
really are, and that the non-ideal particulars we encounter in 
sense-experience are between being and not being. He is often 
taken to be saying that only Ideas really exist, and that tangible 
objects are unreal and illusory. In context, it is clear that when 
Plato says that only Ideas really are, he does not mean that only 
Ideas really exist, but that only the Idea of F is really F, whatever 
F may be in the particular case. Particulars are between being 
and not being in that they are between being F and not being F
—i.e. they are sometimes F and sometimes not F.27
For instance, only the Idea of Beauty is really beautiful, because 
particular beautiful things are (a) beautiful in one respect but 
ugly in another (in figure, say, but not in complexion), or (b) 
beautiful at one time but not another (e.g. at age 20 but not at 
age 70), (c) beautiful by comparison with some things, but not 
with others (e.g. Helen may be beautiful by comparison with 
Medea, but not by comparison with Aphrodite), (d) beautiful in 
some surroundings but not in others (Smp. 211 a—e).
An important feature of the classical Theory of Ideas is the 
Principle of Sublimity. The particulars that participate belong to 
the inferior world of Becoming, the world of change and decay; 
the Ideas that are participated in belong to a superior world of 
Being, of eternal stability. The most sublime of all Ideas is the 
Idea of the Good, superior in rank and power to all else, from 
which everything that can be known derives its being (Rep. 
509c).
The problem with the Theory of Ideas is that the principles that 
define it do not seem to be all consistent with each other. It is 
difficult to reconcile the Principle of Separation with the 
Princip27le Is fi orsft  Cleoamrnmt tohnisa lfirtoym a Vnldas toofs ’Sse alrfPtirceled ‘icDaetgiroene.s  Tohf eR edailffiityc iunl ty 
wasP filartsot’ ,e inx pRo. uBnadmebdro buyg hP (leadto.) , hNiemws Eeslsfa iyns otnh ePl aPtoa ramnde Anrisdteotsle,  where 
he g(Livoensd oann:  Raorugtulemdegne t& a Kloengagn t Phaeu lf,o 1ll9o6w5i)n. g lines. Let us suppose 
that we have a number of particulars, each of which is F. The5n3, 
by (1) there is an Idea of F. This, by (3), is itself F. But now the 
Idea of F and the original particular Fs make up a new collection 
of F things. By (1) again, this
PYTHAGORAS TO PLATO
must be because they participate in an Idea of F. But by (2) this 
cannot be the Idea first postulated. So there must be another 
Idea of F; but this in turn, by (3), will be F, and so on ad 
infinitum. If we are to avoid this regress, we must abandon one 
or other of the principles that generate it. To this day scholars 
are divided as to how seriously Plato took this difficulty, and 
which, if any, of his principles he modified in order to solve it. I 
shall return to the question when we engage in a fuller 
discussion of Plato’s metaphysics.28
Plato applied his Theory of Ideas to many philosophical 
problems: he offered them as the basis of moral values, the 
bedrock of scientific knowledge, and the ultimate origin of all 
being. One problem to which Plato offered his theory as an 
answer is often called the problem of universals: the problem of 
the meaning of universal terms such as ‘man’, ‘bed’, ‘virtue’, 
‘good’. Because Plato’s answer turned out to be unsatisfactory, 
the problem was to remain on the philosophical agenda. In 
succeeding chapters we shall see how Aristotle handled the 
issue. The problem had a continuing history through the Middle 
Ages and up to our own time. A number of notions that occur in 
modern discussions of the problem bear a resemblance to 
Plato’s Ideas.
Predicates. In modern logic a sentence such as ‘Socrates is wise’ 
is considered as having a subject, ‘Socrates’, and a predicate, 
which consists of the remainder of the sentence, i.e. ‘...is wise’. 
Some philosophers of logic, following Gottlob Frege, have 
regarded predicates as having an extramental counterpart: an 
objective predicate (Frege called it a ‘function’) corresponding to 
‘...is a man’ in a way similar to that in which the man Socrates 
corresponds to the name ‘Socrates’. Frege’s functions, such as 
the function x is a man, are objective entities: they are more like 
the fifth items of the Seventh Letter than like the fourth items. 
They share some of the transcendental properties of Ideas: the 
function x is a man does not grow or die as human beings do, 
and nowhere in the world can one view or handle the function x 
is divisible by 7. But functions do not conform to the Principles of 
Self-Predication or Uniqueness. How could one ever im2a8 gSienee p t.h 2a0t8 ff below.
the function x is a man, and only that function, was really and 
t5r4uly a human being?
Classes. Functions serve as principles according to which objects 
can be collected into classes: objects that satisfy the function x 
is human, for
PYTHAGORAS TO PLATO
instance, can be grouped into the class of human beings. Ideas 
in some way resemble classes: participation in an Idea can be 
assimilated to membership of a class. The difficulty in identifying 
Ideas with classes arises again over the Principle of Self-
Predication. The class of men is not a man and we cannot say in 
general that the class of Fs is F. However, it seems at first sight 
as if there are, indeed, some classes that are members of 
themselves, such as the class of classes. But just as Plato was to 
find that the Principle of SelfPredication led him into serious 
problems, so modern philosophers discovered that if one was 
allowed total freedom to form classes of classes one would be 
led into paradoxes. Most notorious is the paradox of the class of 
all classes that are not members of themselves. Bertrand Russell 
pointed out that if this class is a member of itself it is not a 
member of itself, and if it is not a member of itself then it is a 
member of itself. It is no accident that Russell’s paradox bears a 
striking resemblance to Plato’s self-criticism in the Parmenides.
Paradigms. It has more than once been suggested that Platonic 
Ideas might be looked on as paradigms or standards: the 
relation between individuals and Ideas might be thought to be 
similar to that between metre-long objects and the Standard 
Metre by which the metre length was formerly defined.29 This 
notion fits well the way in which for Plato particulars imitate or 
resemble Ideas: to be a metre long was, precisely, to resemble 
the Standard Metre, and if two things were each a metre long it 
was in virtue of their common resemblance to the paradigm. 
However, such paradigms fail the Principle of Sublimity: the 
Standard Metre was not in heaven but in Paris.
Concrete universals. Philosophers have sometimes toyed with 
the notion that in a sentence such as ‘Water is fluid’ the word 
‘water’ is to be treated as the name of a single scattered object, 
the aqueous portion of the world, made up of puddles, rivers, 
lakes, and so on. This would give a clear sense to Plato’s 
principle that particulars participate in Ideas: this particular 
bottle of water is quite literally apart of all-the-water-in-the-
world.2 M9 oTrheeo ivdeera,  owriagtienra tiesd u wnidtho uWbittetgdelyn swteainte. rS,e aen Pd.  Tn.o Gtheiancgh ,t ‘hTahte  is 
not wThaitredr M isa nr eAaglalyin ’a, nind  Rt.r uE.l yA lwleant (eerd. .T),h Sistu dnioest iionn P latlos’os  Mseutiatpsh Pyslaictso ’s 
prefe(Lroenndcoen (: nRootu toleftdegne  s&h Kaeregdan b Pya uhli,s 1 c9o6m5).mentators) for referring 
to Ideas by a concrete mode of speech (e.g. 55
PYTHAGORAS TO PLATO
‘the beautiful’) rather than an abstract one (e.g. ‘beauty’). 
However, concrete universals fail the Principle of Sublimity and 
the Principle of Purity: the water in the universe can be located 
and can change in quantity and distribution, and it has many 
other properties besides that of being water.
None of these notions do full justice to the many facets of Plato’s 
Ideas. If one wants to see how his six principles seemed 
plausible to Plato it is better to consider, not any modern 
logician’s technical concept, but some more unreflective notion. 
Consider the points of the compass, north, south, west, and east. 
Take the notion, say, of the east as one might conceive it by 
naive reflection on the various idioms we in Britain use about the 
east. There are many places that are east of us, e.g. Belgrade 
and Hong Kong. Anything thus eastward is part of the east 
(participation) and is in the same direction as the east 
(imitation). That is what makes whatever is east of us east (1). 
The east, however, cannot be identified with any point in space, 
however eastward it may be (2). The east is of course east of us 
(3), and the east is nothing but east (4): if we say ‘The east is 
red’ we only mean that the eastern sky is red. Nothing but the 
east is unqualifiedly east: the sun is sometimes east and 
sometimes west, India is east of Iran but west of Vietnam, but in 
every time and place the east is east (5). The east has no history 
in time, and it cannot be seen, handled, or parcelled out (6).
I am not, of course, suggesting that points of the compass will 
supply an interpretation of Plato’s principles that will make them 
all come out true: no interpretation could do that since the 
principles form an inconsistent set. I am merely saying that this 
interpretation will make the theses look prima facie plausible in 
a way that the interpretations previously considered will not. 
Functions, classes, paradigms, and concrete universals all raise 
problems of their own, as philosophers long after Plato 
discovered, and though we  cRaenpnoutb lgico back to the classical Plato’s
Theory of Ideas, we have yet to give a fully satisfactory answer 
tIno tPhlea tpor’os bmleomsst ifta wmaosu ms edaianlto tgou aed, dtrhees sR. epublic, the Theory of 
Ideas is put to use not only for the logical and semantical 
purposes that we have just been considering, but also to 
address problems in epistemology, metaphysics,
56
PYTHAGORAS TO PLATO
and ethics. These ramifications of the theory will be considered 
in later chapters. But the Republic is best known to the world at 
large not for its manifold exploitation of the theory, but for the 
political arrangements that are described in its central books.
The official topic of the dialogue is the nature and value of 
justice. After several candidate definitions for justice have been 
examined and found wanting in the first book (which probably 
originally existed as a separate dialogue), the main part of the 
work begins with a challenge to Socrates to prove that justice is 
something worthwhile for its own sake. Plato’s brothers Glaucon 
and Adeimantus, who are characters in the dialogue, argue that 
justice is chosen as a way of avoiding evil. To avoid being 
oppressed by others, Glaucon says, weak human beings make 
compacts with each other neither to suffer nor to commit 
injustice. People would much prefer to act unjustly if they could 
do so with impunity—the kind of impunity a man would have, for 
instance, if he could make himself invisible so that his misdeeds 
passed undetected. Adeimantus supports his brother, saying 
that among humans the rewards of justice are the rewards of 
seeming to be just rather than the rewards of actually being just, 
and with regard to the gods the penalties of injustice can be 
bought off by prayer and sacrifice (2. 358a—367e).
We shall see in Chapter 8 how Socrates responds, through the 
remaining books of the dialogue, to this initial challenge. Now, in 
the interests of setting out Plato’s political philosophy, we should 
concentrate on his immediate response. To answer the brothers 
he shifts from the consideration of justice, or righteousness, in 
the individual person to the larger issue of justice in the city-
state. There, he says, the nature of justice will be written in 
bigger letters and therefore easier to read. The purpose of living 
in cities is to enable people with different skills to supply each 
other’s needs by an appropriate division of labour. Ideally, if 
people were content as they once were with the satisfaction of 
their basic needs, a very simple community would suffice. But in 
the modern luxurious age citizens demand more than mere 
subsistence, and this necessitates more complicated political 
arrangements, including a well-trained professional army (2. 
369b—374d).
Socrates now presents a blueprint for a city with three classe5s7. 
Those among the soldiers best fitted to rule are selected by 
competition to form the upper class, called guardians; the 
remaining soldiers are described as auxiliaries, and the rest of 
the citizens belong to the class of farmers and
PYTHAGORAS TO PLATO
artisans (2. 374d—376e). How are the working classes to be 
brought to accept the authority of the ruling classes? A myth 
must be propagated, a ‘noble falsehood’, to the effect that 
members of the three classes have different metals in their soul: 
gold, silver, and bronze respectively. Citizens in general are to 
remain in the class in which they were born, but Socrates allows 
a limited amount of social mobility (3. 414c—415c).
The rulers and auxiliaries are to receive an elaborate education 
in literature (based on a bowdlerized Homer), music (provided it 
is martial and edifying), and gymnastics (undertaken by both 
sexes in common) (2. 376e—3. 403b). Women as well as men 
are to be guardians and auxiliaries, but this involves severe 
restraints no less than privileges. Members of the upper classes 
are not allowed to marry; women are to be held in common and 
all sexual intercourse is to be public. Procreation is to be strictly 
regulated on eugenic grounds. Children are not to be allowed 
contact with their parents, but will be brought up in public 
creches. Guardians and auxiliaries may not own property or 
touch money; they will be given, free of charge, adequate but 
modest provisions, and they will live in common like soldiers in a 
camp (5. 451d—471c).
The state that Socrates imagines in books 3 to 5 of the Republic 
has been both denounced as a piece of ruthless totalitarianism 
and admired as an early exercise in feminism. If it was ever 
seriously meant as a blueprint for a real-life polity, then it must 
be admitted that it is in many respects in conflict with the most 
basic human rights, devoid of privacy and full of deceit. 
Considered as a constitutional proposal, it deserves all the 
obloquy that has been heaped on it by conservatives and 
liberals alike. But it must be remembered that the explicit 
purpose of this constitution-mongering was to cast light on the 
nature of justice in the soul, as Socrates goes on to do.30 Plato, 
we know from other dialogues, delighted in teasing his readers; 
he extended the irony he had learnt from Socrates into a major 
principle of philosophical illumination.
However, having woven the analogy with his classbound state 
into his moral psychology, Pla30to S eine  Claht.e 7r  bbeoloowk.s of the Republic 
returns to political theory. His ideal state, he tells us, 
i5n8corporates all the cardinal virtues: the virtue of wisdom 
resides in the guardians, fortitude in the auxiliaries, temperance 
in the working classes, and justice is rooted in the principle of 
the division of labour from which the city-state took its origin. In 
a just
PYTHAGORAS TO PLATO
SHpHvtvm# / mi. V
® “fi• W ■ 19
itfV
Despite Plato’s proposals, it was rare for a woman to be admitted to a 
philosophical school as Hipparchia is here shown, in a fourth-century-BC 
fresco, joining her husband, Crates, founder of the Cynics
state every citizen and every class does that for which they are 
most suited, and there is harmony between the classes (4. 427d
—434c).
In less ideal states there is a gradual falling away from this ideal. 
There are five possible types of political constitution (8. 544e). 
The first and best constitution is called monarchy or aristocracy: 
if wisdom rules it does not matter whether it is incarnate in one 
or many rulers. There are four other inferior types of 
constitution: timocracy, oligarchy, democracy, and despotism 
(8. 543c). Each of these constitutions declines into the next 
because of the downgrading of one of the virtues of the ideal 
state. If the rulers cease to be persons of wisdom, aristocracy 
gives place to timocracy, which is essentially rule by a military 
junta (8. 547c). Oligarchy differs from timocracy because 
oligarchic rulers lack fortitude and military virtues (8. 556d5)9. 
Oligarchs do possess, in a rather miserly form, the virtue of 
temperance; when this is
PYTHAGORAS TO PLATO
abandoned oligarchy gives way to democracy (8. 555b). For 
Plato, any step from the aristocracy of the ideal republic is a 
step away from justice; but it is the step from democracy to 
despotism that marks the enthronement of injustice incarnate 
(8. 576a). So the aristocratic state is marked by the presence of 
all the virtues, the timocratic state by the absence of wisdom, 
the oligarchic state by the decay of fortitude, the democratic 
state by contempt for temperance, and the despotic state by the 
overturning of justice.
Plato recognizes that in the real world we are much more likely 
to encounter the various forms of inferior state than the ideal 
constitution described in the Republic. Nonetheless, he insists 
that there will be no happiness, public or private, except in such 
a city, and such a city will never be brought about unless 
philosophers become kings or kings become philosophers (5. 
473c—d). Becoming a philosopher, of course, involves working 
through Plato’s educational system in order to reach 
acquaintance withT hthee L Iadewass .and the Timaeus
Later in his life Plato abandoned the idea of the philosopher king 
and ceased to treat the Theory of Ideas as having political 
significance. He came to believe that the character of the ruler 
was less important to the welfare of a city than the nature of the 
laws under which it was governed. In his late and longest work, 
the Laws, he portrays an Athenian visitor discussing with a 
Cretan and a Spartan the constitution of a colony, Magnesia, to 
be founded in the south of Crete. It is to be predominantly 
agricultural, with the free population consisting mainly of citizen 
farmers. Manual work is done largely by slaves, and craft and 
commerce are the province of resident aliens. Full citizenship is 
restricted to 5,040 adult males, divided into twelve tribes. The 
blueprint for government that is presented as a result of the 
advice of the Athenian visitor stands somewhere between the 
actual constitutional arrangements of Athens and the imaginary 
structures of Plato’s ideal republic.
Like Athens, Magnesia is to have an assembly of adult male 
citizens, a Council, and a set of elected officials, to be called the 
Guardians of the Laws. Ordinary citizens will take part in the 
6a0dministration of the laws by sitting on enormous juries. Various 
appointments are made by lot, so as to
PYTHAGORAS TO PLATO
ensure wide political participation. Private property is allowed, 
subject to a highly progressive wealth tax (5. 744b). Marriage, 
far from being abolished, is imposed by law, and bachelors over 
35 have to pay severe annual fines (6. 774b). Finally, legislators 
must realize that even the best laws are constantly in need of 
reform (6. 769d).
On the other hand, Magnesia has several features reminiscent of 
the Republic. Supreme power in the state rests with a Nocturnal 
Council, which includes the wisest and most highly qualified 
officials, specially trained in mathematics, astronomy, theology, 
and law (though not, like the guardians of the Republic, 
metaphysics). Private citizens are not allowed to possess gold or 
silver coins, and the sale of houses is strictly forbidden (5. 740c, 
742a). Severe censorship is imposed on both texts and music, 
and poets must be licensed (7. 801d—2a). Female sex police, 
with right of entry to households, oversee procreation and 
enforce eugenic standards (6. 784a—b). In divorce courts there 
must be as many women judges as men (9. 930a). Women are 
to join men at the communal meals, and they are to receive 
military training, and provide a home defence force (7. 814a). 
Education is of great importance for all classes, and is to be 
supervised by a powerful Minister of Education reporting direct 
to the Nocturnal Council (6. 765d).
Substantive legislation is set out in the middle books of the 
dialogue. Each law must have a preamble setting out its 
purpose, so that citizens may conform to it with understanding. 
For instance, a law compelling marriage between the age of 30 
and 35 should have a preamble explaining that procreation is 
the method by which human beings achieve immortality (4. 
721b). The duties of the many administrative officials are set out 
in book 6, and the educational curriculum is detailed, from 
playschool upward, in book 7; the Laws itself is to be a set 
school text. Book 9 deals with forms of assault and homicide and 
sets out the procedure relating to capital offences such as 
temple robbery. Elaborate provision is made to ensure that the 
accused gets a fair trial. In civil matters the law goes into fine 
detail, laying down, for instance, the damages to be paid by a 
defendant who is shown to have enticed away bees from the 
plaintiff s hive (9. 843e). Hunting is to be very severe6l1y 
restricted: the only form allowed is the hunting of fourlegged 
animals, on horseback, with dogs (7. 824a).
From time to time in the Laws Plato engages in theoretical 
discussion of sexual morality, though actual sexual legislation is 
restricted to a form of excommunication for adultery (7. 785d—
e). In a way that has been very
PYTHAGORAS TO PLATO
common during the Christian era, but was rare in pagan 
antiquity, he bases his sexual ethics on the notion that 
procreation is the natural purpose of sex. The Athenian says at 
one point that he would like to put into effect ‘A law to permit 
sexual intercourse only for its natural purpose, procreation, and 
to prohibit homosexual relations; to forbid the deliberate killing 
of a human offspring and the casting of seed on rocks and stone 
where it will never take root and fructify’ (8. 838e). He realizes, 
however, that it will be very difficult to ensure compliance with 
such a law, and instead he proposes other measures to stamp 
out sodomy and discourage all forms of non-procreative 
intercourse (8. 836e, 841d). We have reached a point in Plato’s 
thinking far distant from the arch homosexual banter which is 
such a predominant feature of the Socratic dialogues.
One of the most interesting sections of the Laws is the tenth 
book, which deals with the worship of the gods and the 
elimination of heresy. Impiety arises, the Athenian says, when 
people do not believe that the gods exist, or believe that they 
exist but do not care for the human race. As a preamble to laws 
against impiety, therefore, the lawgiver must establish the 
existence of the divine. The elaborate argument he presents will 
be considered in a later chapter on philosophy of religion.
In the Timaeus, a dialogue whose composition probably 
overlapped with that of the Laws, Plato sets out the relationship 
between God and the world we live in. He returns to the 
traditional philosophical topic of cosmology, taking it up at the 
point where Anaxagoras had, in his view, left off unsatisfactorily. 
The world of the Timaeus is not a field of mechanistic causes: it 
is fashioned by a divinity, variously called its father, its maker, or 
its craftsman (demiourgos) (28c).
Timaeus, the eponymous hero of the dialogue, is an astronomer. 
He offers to narrate to Socrates the history of the universe, from 
the origin of the cosmos to the appearance of mankind. People 
ask, he says, whether the world has always existed or whether it 
had a beginning. The answer must be that it had a beginning, 
because it is visible, tangible, and corporeal, and nothing that is 
perceptible by the senses is eternal and changeless in the way 
that the objects of thought are (27d—28c). The divinity who 
f6a2shioned it had his eye on an eternal archetype, ‘for the cosmos 
is the most beautiful of the things that have come to be, and he 
is the best of all causes’ (29a). Why did he bring it into 
existence? Because he was good, and what is good is utterly 
free from envy or selfishness (29d).
PYTHAGORAS TO PLATO
Like the Lord God in Genesis, the maker of the world looked at 
what he had made and found that it was good; and in his delight 
he adorned it with many beautiful things. But the Demiurge 
differs from the creator of Judaeo-Christian tradition in several 
ways. First of all, he does not create the world from nothing: 
rather, he brings it into existence from a primordial chaos, and 
his creative freedom is limited by the necessary properties of the 
initial matter (48a). ‘God, wishing all things to be good and 
nothing, if he could help it, paltry, and finding the visible 
universe in a state not of peace but of inharmonious and 
disorderly motion, brought it from disorder into an order that he 
judged to be altogether better’ (30a). Secondly, while the Mosaic 
creator infuses life into an inert world at a certain stage of its 
creation, in Plato both the ordered universe and the archetype 
on which it was patterned are themselves living beings. What is 
this living archetype? He does not tell us, but perhaps it is the 
world of Ideas which, he concluded belatedly in the Sophist, 
must contain life. God created the soul of the world before he 
formed the world itself: this world-soul is poised between the 
world of being and the world of becoming (35a). He then 
fastened the world on to it.
The soul was woven all through from the centre to the outermost 
heaven, which it wrapped itself around. By its own revolution upon 
itself it provided a divine principle of unending and rational life for all 
time. The body of the heaven was made visible, but the soul is invisible 
and endowed with reason and harmony. It is the best creation of the 
best of intelligible and eternal realities. (36e—37a)
In contrast to those earlier philosophers who spoke ofmultiple 
worlds, Plato is very firm that our universe is the only one (31b). 
He follows Empedocles in regarding the world as made up of the 
four elements, earth, air, fire, and water, and he follows 
Democritus in believing that the different qualities of the 
elements are due to the different shapes of the atoms that 
constitute them. Earth atoms are cubes, air atoms are 
octahedrons, fire atoms are pyramids, and water atoms are 
icosahedrons. Pre-existent space was the receptacle into which 
the maker placed the wo31r lSde, ea Cnhd.  i5n b ae lmowy.sterious way it underlies 
the transmutation of the four elements, rather as a lump of gold 
underlies the different shapes that a jeweller may give to6 3it 
(50a). In this Plato seems to anticipate the prime matter of 
Aristotelian hylomorphism.31
PYTHAGORAS TO PLATO
Timaeus explains that there are four kinds of living creatures 
in the universe: gods, birds, animals, and fish. Among gods Plato 
distinguishes between the fixed stars, which he regards as 
everlasting living beings, and the gods of Homeric tradition, 
whom he mentions in a rather embarrassed aside. He describes 
the infusion of souls into the stars and into human beings, and 
he develops a tripartite division of the human soul that he had 
introduced earlier in the Republic. He gives a detailed account of 
the mechanisms of perception and of the construction of the 
human body.32 This construction, he tells us, was delegated by 
God to the lesser divinities that he had himself made personally 
(69c). A full description is given of all our bodily organs and their 
function, and there is a listing of diseases of body and mind.
The Timaeus was for centuries the most influential of Plato’s 
dialogues. While the other dialogues went into oblivion between 
the end of antiquity and the beginning of the Renaissance, much 
of the Timaeus survived in Latin translations by Cicero and a 
fourth-century Christian called Chalcidius. Plato’s teleological 
account of the forming of the world by a divinity was not too 
difficult for medieval thinkers to assimilate to the creation story 
of Genesis. The dialogue was a set text in the early days of the 
University of Paris, and 300 years later Raphael in his School of 
Athens gave Plato in the3 2c eSneter eC ho. f7 t hbeel ofrwe.sco only the Timaeus to 
hold.
64
2
Schools of Thought: 
From Aristotle to 
Augustine
The fourth century saw a shift in political power from the city-
states of classical Greece to the kingdom of Macedonia to the 
north. In the same way, after the Athenians Socrates and Plato, 
the next great philosopher was a Macedonian. Aristotle was 
born, fifteen years after Socrates’ death, in the small colony of 
Stagira, on the peninsula of Chalcidice. He was the son of 
Nicomachus, court physician to King Amyntas, the grandfather 
of Alexander the Great. After the death of his father he migrated 
to Athens in 367, being then 17, and joined Plato’s Academy. He 
remained for twenty years as Plato’s pupil and colleague, and it 
can safely be said that on no other occasion in history was such 
intellectual power concentrated in a single institution.
Aristotle in the Academy
Many of Plato’s later dialogues date from these decades, and 
some of the arguments they contain may reflect Aristotle’s 
contributions to debate. By a flattering anachronism, Plato 
introduces a character called Aristotle into the Parmenides, the 
dialogue that contains the most acute criticisms of the Theory of 
Ideas. Some of Aristotle’s own writings also belong to this 
period, though many of these early works survive only in 
fragments quoted by later writers. Like his master, he wrote 
initially in dialogue form, and in content his dialogues show a 
strong Platonic influence.
ARISTOTLE TO AUGUSTINE
The location of the philosophical schools of Athens
In his lost dialogue Eudemus, for instance, Aristotle 
expounded a conception of the soul close to that of Plato’s 
Phaedo. He argued vigorously against the thesis that the soul is 
an attunement of the body, claiming that it is imprisoned in a 
carcass and capable of a happier life when disembodied. The 
dead are more blessed and happier than the living, and have 
become
66
ARISTOTLE TO AUGUSTINE
greater and better. ‘It is best, for all men and women, not to be 
born; and next after that—the best option for humans—is, once 
born, to die as quickly as possible’ (fr. 44). To die is to return to 
one’s real home.
Another Platonic work of Aristotle’s youth is his Protrepticus, or 
exhortation to philosophy. This too is lost, but it was so 
extensively quoted in later antiquity that some scholars believe 
they can reconstruct it almost in its entirety. Everyone has to do 
philosophy, Aristotle says, for arguing against the practice of 
philosophy is itself a form of philosophizing. But the best form of 
philosophy is the contemplation of the universe of nature. 
Anaxagoras is praised for saying that the one thing that makes 
life worth living is to observe the sun and the moon and the 
stars and the heavens. It is for this reason that God made us, 
and gave us a godlike intellect. All else—strength, beauty, 
power, and honour—is worthless (Barnes, 2416).
The Protrepticus contains a vivid expression of the Platonic view 
that the soul’s union with the body is in some way a punishment 
for evil done in an earlier life. ‘As the Etruscans are said often to 
torture captives by chaining corpses to their bodies face to face, 
and limb to limb, so the soul seems to be spread out and nailed 
to all the organs of the body’ (ibid.). All this is very different 
from Aristotle’s eventual mature thought.
It is probable that some of Aristotle’s surviving works on logic 
and disputation, the Topics and Sophistical Refutations, belong to 
this period. These are works of comparatively informal logic, the 
one expounding how to construct arguments for a position one 
has decided to adopt, the other showing how to detect 
weaknesses in the arguments of others. Though the Topics 
contains the germ of conceptions, such as the categories, that 
were to be important in Aristotle’s later philosophy, neither work 
adds up to a systematic treatise on formal logic such as we are 
to be given in the Prior Analytics. Even so, Aristotle can say at the 
end of the Sophistical Refutations that he has invented the 
discipline of logic from scratch: nothing at all existed when he 
started. There are many treatises on rhetoric, he says, but
on the subject of deduction we had nothing of an earlier date to cite, 
but needed to spend a long time on original research. If, then, it seems 
to you on inspection that from such an unpromising start we ha6v7e 
brought our investigation to a satisfactory condition comparable to that 
of traditional disciplines, it falls to you my students to grant me your 
pardon for the shortcomings of the inquiry, and for its discoveries your 
warm thanks. (SE 34. 184a9—b8)
ARISTOTLE TO AUGUSTINE
It is indeed one of Aristotle’s many claims on posterity that he 
was logic’s founder. His most important works on the subject are 
the Categories, the de Interpretation, and the Prior Analytics. 
These set out his teaching on simple terms, on propositions, and 
on syllogisms. They were grouped together, along with the two 
works already mentioned, and a treatise on scientific method, 
the Posterior Analytics, into a collection known as the Organon, 
or ‘tool’ of thought. Most of Aristotle’s followers thought of logic 
not as itself a scientific discipline, but as a propaedeutic art 
which could be used in any discipline; hence the title. The 
Organon, though shown already in antiquity to be incomplete as 
a system of logic, was regarded for two millennia as providing 
the core of the subject.1
While Aristotle was at the Academy, King Philip II of Macedon, 
who succeeded his father in 359, adopted an expansionist policy 
and waged war on a number of Greek city-states, including 
Athens. Despite the martial eloquence of Aristotle’s 
contemporary Demosthenes, who denounced the Macedonian 
king in his ‘Philippics’, the Athenians defended their interests 
only half-heartedly. After a series of humiliating concessions 
they allowed Philip to become, by 338, master of the Greek 
world. It cannot have been an easy time to be a Macedonian 
resident in Athens.
Within the Academy, however, relations seem to have remained 
cordial. Later generations liked to portray Plato and Aristotle 
embattled against each other, and some in antiquity likened 
Aristotle to an ungrateful colt who had kicked his mother (D.L. 5. 
1). But Aristotle always acknowledged a great debt to Plato, 
whom on his death he described as the best and happiest of 
mortals ‘whom it is not right for evil men even to praise’. He 
took a large part of his philosophical agenda from Plato, and his 
teaching is more often a modification than a repudiation of 
Plato’s doctrines. The philosophical ideas that are common to 
the two philosophers are more important than the issues that 
divide them—just as, in the seventeenth and eighteenth 
centuries, the opposing schools of rationalists and empiricists 
had much more in common withi  Aeriasctoht leo’sth loegr ict hisa cno nwsiidtehr etdh ien  detail in Ch. 3.
philosophers who preceded and followed them.
A68lready, however, during his period at the Academy, Aristotle 
began to distance himself from Plato’s Theory of Ideas. In his 
pamphlet On Ideas he maintained that the arguments of Plato’s 
central dialogues establish only i
ARISTOTLE TO AUGUSTINE
that there are, in addition to particulars, certain common objects 
of the sciences; but these need not be Ideas. He employs 
against Ideas a version of an argument that we have already 
encountered in Plato’s own dialogues— he calls it the ‘Third Man 
argument’ (Barnes, 2435). In his surviving works Aristotle often 
take issue with the theory. Sometimes he does so politely, as 
where, in the Nicomachean Ethics, he introduces a series of 
arguments against the Idea of the Good with the remarks that 
he has an uphill task because the Forms were introduced by his 
good friends. However, his duty as a philosopher is to honour 
truth above friendship. In the Posterior Analytics, however, he 
dismisses Ideas contemptuously as ‘tarradiddle’ (1. 22. 83a33).
More seriously, in his Metaphysics he argues that the theory fails 
to solve the problems it was meant to address. It does not confer 
intelligibility on particulars, because immutable and everlasting 
forms cannot explain how particulars come into existence and 
undergo change. Moreover, they do not contribute anything 
either to the knowledge or to the being of other things (A 9. 991 
a8 ff.). All the theory does is to bring in new entities equal in 
number to the entities to be explained: as if one could solve a 
problem by doubling itA (rAis t9o.t 9le9 t0hbe3 )B. iologist
When Plato died in 347, his nephew Speusippus became head of 
the Academy, and Aristotle left Athens. He migrated to Assos on 
the northwestern coast of what is now Turkey. The city was 
under the rule of Hermias, a graduate of the Academy, who had 
already invited a number of Academicians to form a new 
philosophical institute there. Aristotle became a friend of 
Hermias, and married a close relation of his, Pythias, with whom 
he had two children. In 343 Hermias met a tragic end: having 
negotiated, with Aristotle’s help, an alliance with Macedon, he 
was treacherously arrested and eventually crucified by the Great 
King of Persia. Aristotle saluted his memory in an ‘Ode to Virtue’, 
his only surviving poem.
During his period in Assos, and during the next few years, when 
he lived at Mytilene on the island of Lesbos, Aristotle carried out 
extensive scientific research, particularly in zoology and marine 
biology. These researches were written up in a book later known, 
misleadingly, as the History of Animals, to which he added tw69o 
shorter treatises, On the Parts of Animals and
yUUSTOTELIS UE HISTo 
IUA AN L MALLVM_ UBLR
THEODORE
NIM AW PA 
ll LrS AVT 
IN6*
posltae:
1 N 5 IM I ITS 5 IBI TART E S
The frontispiece of a fifteenth-century manuscript translation of 
Aristotle’s History of Animals
ARISTOTLE TO AUGUSTINE
On the Generation of Animals. Aristotle does not claim to have 
founded the science of zoology, and his books contain copious 
citations of earlier writers, accompanied by a judicious degree of 
scepticism about some of their wilder reports. However, his 
detailed observations of organisms of very various kinds were 
quite without precedent, and in many cases they were not 
superseded until the seventeenth century.
Though he does not claim to be the first zoologist, Aristotle 
clearly saw himself as a pioneer, and indeed felt some need to 
justify his interest in the subject. Previous philosophers had 
given a privileged place to the observation ofthe heavens, and 
here was he prodding sponges and watching the hatching of 
grubs. In his defence he says that while the heavenly bodies are 
marvellous and glorious, they are hard to study because they 
are so distant and different from ourselves. Animals, however, 
are near at hand, and akin to our own nature, so that we can 
investigate them with much greater precision. It is childish to be 
squeamish about the observation of the humbler animals. ‘We 
should approach the investigation of every kind of animal 
without being ashamed, for each of them will exhibit to us 
something natural and something beautiful’ (PA 1. 5. 645a20—
5).
The scope of Aristotle’s researches is astonishing. Much of his 
work is taken up with classification into genus (e.g. Testacea) 
and species (e.g. sea-urchin). More than 500 species figure in his 
treatises, and many of them are described in detail. It is clear 
that Aristotle was not content with the observation of a 
naturalist: he also practised dissection like an anatomist. He 
acknowledges that he found dissection distasteful, particularly in 
the case of human beings: but it was essential to examine the 
parts of any organism in order to understand the structure of the 
whole (PA 1. 5. 644b22—645a36).
Aristotle illustrated his treatises with diagrams, now sadly lost. 
We can conjecture the kind of illustrations he provided when we 
read passages such as the following, where he is explaining the 
relationship between the testicles and the penis.
In the accompanying diagram the letter A marks the starting 
point of ducts leading down from the aorta; the letters KK mark 
the heads of the testicles and the ducts that descend to them71; 
the ducts leading from them through the testicles are marked 
YY, and the reverse ducts containing white fluid and leading to 
the testicles are marked BB; the penis D, the bladder E, and the 
testicles XX. (HA 3. 1. 510a30—4)
ARISTOTLE TO AUGUSTINE
Only a biologist could check the accuracy of the myriad items of 
information that Aristotle offers us about the anatomy, diet, 
habitat, modes of copulation, and reproductive systems of 
mammals, birds, reptiles, fish, and insects. The twentieth-
century biologist Sir D’Arcy Thompson, who made the canonical 
translation of the History of Animals into English, constantly 
draws attention to the minuteness of his detailed investigations, 
coupled with vestiges of superstition. There are some 
spectacular cases where Aristotle’s unlikely stories about rare 
species of fish were proved accurate many centuries later.2 In 
other places Aristotle states clearly and fairly biological 
problems that were not solved until millennia had passed. One 
such case was the question whether an embryo contained all the 
parts of an animal in miniature form from the beginning, or 
whether wholly new structures were formed as the embryo 
develops (GA 2. 1. 734a1—735a4).
The modern layman can only guess which parts of passages like 
the following are accurate, and which are fantasy.
All animals that are quadrupedal, blooded, and viviparous are 
furnished with teeth; but, to begin with, some have teeth in both 
jaws, and some do not. For instance, horned quadrupeds do not; 
for they have not got the front teeth in the upper jaw; and some 
hornless animals, also, do not have teeth in both jaws, as the 
camel. Some animals have tusks, like the boar; and some have 
not. Further, some animals are saw-toothed, such as the lion, 
the leopard, and the dog; and some have teeth that do not 
interlock, as the horse and the ox; and by ‘saw-toothed’ we 
mean such animals as interlock the sharp-pointed teeth. (HA 2. 
1. 501a8 ff.)
With such fish as pair, eggs are the result of copulation, but such 
fish have them also without copulation; and this is shown in the 
case of some river-fish, for the minnow has eggs when quite 
small—almost, one might say, as soon as it is born. These Wshes 
shed their eggs, and, as is stated, the males swallow the greater 
part of them, and some portion of them goes to waste in the 
water; but such of the eggs as the female deposits in suitable 
places are saved. If all the eggs were preserved, each species 
would be vast in number. The greater number of these eggs are 
not productive, but only those over which the male sheds the 
milt; for when the female has laid her eggs, the male follows and 
sheds its milt over them, and from all the eggs so besprinkled 
y7o2ung fishes proceed, while the rest are left to their fate. (HA 6. 
3. 567a29-b6)
It is easier to form a quick judgement about Aristotle’s attempts 
to link features of human anatomy to traits of character. He tells 
us, for instance,
2 See G. E. R. Lloyd, Aristotle: The Growth and Structure of his Thought 
(Cambridge: Cambridge University Press, 1968), 74-81.
ARISTOTLE TO AUGUSTINE
that those who have flat feet are likely to be rogues, and that 
those who have large and prominent ears have a tendency to 
irrelevant chatter (HA 1. 11. 492a1).
Despite an admixture of old wives’ tales, Aristotle’s biological 
works must strike us as a stupendous achievement, when we 
remember the conditions under which he worked, unequipped 
with any of the aids to investigation that have been at the 
disposal of scientists since the early modern period. He, or one 
of his research assistants, must have been gifted with 
remarkably acute eyesight, since some of the features of insects 
that he accurately reports were not again observed until the 
invention of the microscope. His inquiries were conducted in a 
genuinely scientific spirit, and he is always ready to confess 
ignorance where evidence is insufficient. With regard to the 
reproductive mechanism in bees, for example, he has this to 
say:
The facts have not yet been sufficiently ascertained. If ever they are, 
then we must trust observation rather than theory, and trust theories 
only if their results conform with the observed phenomena. (GA 3. 10. 
760b28—31).
The Lyceum and its Curriculum
About eight years after the death of Hermias, Aristotle was 
summoned to the Macedonian capital by King Philip II as tutor to 
his 13-year-old son, the future Alexander the Great. We know 
little of the content of his instruction: the Rhetoric for Alexander 
that appears in the Aristotelian corpus is commonly regarded as 
a forgery. Ancient sources say that Aristotle did write essays on 
kingship and colonization for his pupil, and gave him his own 
edition of Homer. Alexander is said to have slept with this book 
under his pillow; and when he became king in 336 and started 
upon his spectacular military career, he arranged for biological 
specimens to be sent to his tutor from all parts of Greece and 
Asia Minor.
Within ten years Alexander had made himself master of an 
empire that stretched from the Danube to the Indus and 
included Libya and Egypt. While Alexander was conquering Asia, 
Aristotle was back in Athens, where he established his own 
73
school in the Lyceum, a gymnasium just outside the city 
boundary. Now aged 50, he built up a substantial library, and 
gathered around him a group of brilliant research students, 
called ‘Peripatetics’ from the name of the avenue (peripatos) in 
which they walked
ARISTOTLE TO AUGUSTINE
and held their discussions. The Lyceum was not a private club 
like the Academy; many of the lectures given there were open 
to the general public without fee.
Aristotle’s anatomical and zoological studies had given a new 
and definitive turn to his philosophy. Though he retained a 
lifelong interest in metaphysics, his mature philosophy 
constantly interlocks with empirical science, and his thinking 
takes on a biological cast. Most of the works that have come 
down to us, with the exception of the zoological treatises, 
probably belong to this second Athenian sojourn. There is no 
certainty about their chronological order, and indeed it is 
probable that the main treatises—on physics, metaphysics, 
psychology, ethics, and politics—were constantly rewritten and 
updated. In the form in which they have survived it is possible to 
detect evidence of different layers of composition, though no 
consensus has been reached about the identification or dating 
of these strata.
In his major works Aristotle’s style is very different from that of 
Plato or any of his other philosophical predecessors. In the 
period between Homer and Socrates most philosophers wrote in 
verse, and Plato, writing in the great age of Athenian tragedy 
and comedy, composed dramatic dialogue. Aristotle, an exact 
contemporary of the greatest Greek orator Demosthenes, 
preferred to write in prose monologue. The prose he wrote is 
commonly neither lucid nor polished, though he could compose 
passages of moving eloquence when he chose. It may be that 
the texts we have are the notes from which he lectured; perhaps 
even, in some cases, notes taken at lectures by students 
present. Everything Aristotle wrote is fertile of ideas and full of 
energy; every sentence packs a massive intellectual punch. But 
effort is needed to decode the message of his jagged clauses. 
What has been delivered to us from Aristotle across the 
centuries is a set of telegrams rather than epistles.
Aristotle’s works are systematic in a way that Plato’s never 
were. Even in the Laws, which is the closest to a textbook that 
Plato ever wrote, we flit from topic to topic, and indeed from 
discipline to discipline, in a disconcerting manner. None of the 
other major dialogues can be pigeon-holed as relating to a 
s7i4ngle area of philosophy. It is, of course, anachronistic to speak 
of ‘disciplines’ when discussing Plato: but the anachronism is 
not great because the notion of a discipline, in the modern 
academic sense, is made very explicit by Aristotle in his Lyceum 
period.
ARISTOTLE TO AUGUSTINE
There are three kinds of sciences, Aristotle tells us in the 
Metaphysics (E 1. 1025b25): productive, practical, and 
theoretical sciences. Productive sciences are, naturally enough, 
sciences that have a product. They include engineering and 
architecture, with products like bridges and houses, but also 
disciplines such as strategy and rhetoric, where the product is 
something less concrete, such as victory on the battlefield or in 
the courts. Practical sciences are ones that guide behaviour, 
most notably ethics and politics. Theoretical sciences are those 
that have no product and no practical goal, but in which 
information and understanding is sought for its own sake.
There are three theoretical sciences: physics, mathematics, 
and theology (Metaph. E 1. 1026a19). In this trilogy only 
mathematics is what it seems to be. ‘Physics’ means natural 
philosophy or the study of nature (physis). It is a much broader 
study than physics as understood nowadays, including chemistry 
and meteorology and even biology and psychology. ‘Theology’ 
is, for Aristotle, the study of entities above and superior to 
human beings, that is to say, the heavenly bodies as well as 
whatever divinities may inhabit the starry skies. His writings on 
this topic resemble a textbook of astronomy more than they 
resemble any discourse on natural religion.
It may seem surprising that metaphysics, a discipline 
theoretical par excellence, does not figure in Aristotle’s list of 
theoretical sciences, since so much of his writing is concerned 
with it, and since one of his longest treatises bears the title 
Metaphysics. The word, in fact, does not occur in Aristotle’s own 
writings and first appears in the posthumous catalogue of his 
works. It simply means ‘after physics’ and refers to the works 
that were listed Aarifstteort lhei so nP hRyhseitcosr.i cB aunt dh Peo edtidry in fact come to 
recognize the branch of philosophy we now call ‘metaphysics’: 
hIne  tchael lereda iltm ‘F oirfs tp Prohdiluocstoivpeh ys’ caienndc ehse  Adreifistnoetdle  itw aros teth etw doi swcioprliknse,  
tthaet  Rshtuedtoiersic B aenindg  tahse  BPeoinegti.c3s, designed to assist barristers and 
playwrights in their respective tasks. Rhetoric, Aristotle says, is 
the discipline that indicates in any given case the possible 
means of persuasion: it is not restricted to a
3 See Ch. 5 below.
75
ARISTOTLE TO AUGUSTINE
particular field, but is topic-neutral. There are three bases of 
persuasion by the spoken word: the character of the speaker, 
the mood of the audience, and the argument (sound or spurious) 
of the speech itself. So the student of rhetoric must be able to 
reason logically, to evaluate character, and to understand the 
emotions (1. 2. 1358a1—1360b3).
Aristotle wrote more instructively about logic and character in 
other treatises, but the second book of the Rhetoric contains his 
fullest account of human emotions. Emotions, he says, are 
feelings that alter people’s judgements, and they are 
accompanied by pain and pleasure. He takes each major 
emotion in turn, offering a definition of the emotion and a list of 
its objects and causes. Anger, for instance, he defines as a 
desire, accompanied by pain, for what appears to be revenge for 
what appears to be an unmerited slight upon oneself or one’s 
friends (2. 2. 1378a32—4). He gives a long list of the kinds of 
people who make us angry: those who mock us, for instance, or 
those who stop us drinking when we are thirsty, or those who 
get in our way at work.
Also those who speak ill of us, and show contempt for us, in 
respect of the things we most care about. Thus those who seek a 
reputation as philosophers get angry with those who show 
disdain for their philosophy; those who pride themselves upon 
their appearance get angry with those who disparage it, and so 
on. We feel particularly angry if we believe that, either in fact or 
in popular belief, we are totally or largely lacking in the 
respective qualities. For when we are convinced that we excel in 
the qualities for which we are mocked, we can ignore the 
mockery. (2. 2. 1379a32-T)
Aristotle takes us on a detailed tour of the emotions of anger, 
hatred, fear, shame, pity, indignation, envy, and jealousy. In 
each case his treatment is clear and systematic, and often 
shows—as in the above passage—acute psychological insight.
The Poetics, unlike the Rhetoric, has been very widely read 
throughout history. Only its first book survives, a treatment of 
epic and tragic poetry. The second book, on comedy, is lost. 
Umberto Eco, in The Name of the Rose, wove a dramatic fiction 
around its imagined survival and then destruction in a 
fourteenth-century abbey.
T76o understand Aristotle’s message in the Poetics one must know 
something of Plato’s attitude to poetry. In the second and third 
books of the Republic Homer is attacked for misrepresenting the 
gods and for encouraging debased emotions. The dramatic 
representations of the tragedians,
ARISTOTLE TO AUGUSTINE
too, are attacked as deceptive and debasing. In the tenth book 
the Theory of Ideas provides the basis for a further, and more 
fundamental, attack on the poets. Material objects are imperfect 
copies of the truly real Ideas; artistic representations of material 
objects are therefore at two removes from reality, being 
imitations of imitations (597e). Drama corrupts by appealing to 
the lower parts of our nature, encouraging us to indulge in 
weeping and laughter (605d—6c). Dramatic poets must be kept 
away from the ideal city: they should be anointed with myrrh, 
crowned with laurel, and sent on their way (398b).
One of Aristotle’s aims was to resolve this quarrel between 
poetry and philosophy. Imitation, he says, so far from being the 
degrading activity that Plato describes, is something natural to 
humans from childhood. It is one of the features that makes men 
superior to animals, since it vastly increases their scope for 
learning. Secondly, representation brings a delight all of its own: 
we enjoy and admire paintings of objects which in themselves 
would annoy or disgust us (Po. 4. 1448b5—24).
Aristotle offers a detailed analysis of the nature of tragic drama. 
He defines tragedy in the following terms.
A tragedy is a representation of a grand, complete, and 
significant action, in language embellished appropriately in the 
different parts of the work, in dramatic, not narrative form, with 
episodes arousing pity and fear so as to achieve purification 
(katharsis) of these emotions. (6. 144^24 ff.).
No one is quite sure what Aristotle meant by katharsis, or 
purification. Perhaps what he wanted to teach is that watching 
tragedy helps us to put our own sorrows and worries into 
perspective, as we observe the catastrophes that have 
overtaken people who were far superior to the likes of ourselves. 
Pity and fear, the emotions to be purified, are most easily 
aroused, he says, if the tragedy exhibits people as the victims of 
hatred and murder where they could most expect to be loved 
and cherished. That is why so many tragedies concern feuds 
within a single family (14. 1453bl—21).
Six things, Aristotle says, are necessary for a tragedy: plot, 
character, diction, thought, spectacle, and melody (6. 145041 
ff.). It is the first two of these that chiefly interest him. Stage 
setting and musical accompaniment are dispensab7l7e 
accessories: what is great in a tragedy can be appreciated from 
a mere reading of the text. Thought and diction are more 
important:
ARISTOTLE TO AUGUSTINE
it is the thoughts expressed by the characters that arouse 
emotion in the hearer, and if they are to do so successfully they 
must be presented convincingly by the actors. But it is character 
and plot that really bring out the genius of a tragic poet, and 
Aristotle devotes a long chapter to character, and no less than 
five chapters to plot.
The main character or tragic hero must be neither supremely 
good nor supremely bad: he should be a person of rank who is 
basically good, but comes to grief through some great error 
(hamartia). A woman may have the kind of goodness necessary 
to be a tragic heroine, and even a slave may be a tragic subject. 
Whatever kind of person is the protagonist, it is important that 
he or she should have the qualities appropriate to them, and 
should be consistent throughout the drama. (15. 1454a15 ff.). 
Every one of the dramatis personae should possess some good 
features; what they do should be in character, and what 
happens to them should be a necessary or probable outcome of 
their behaviour.
The most important element of all is plot: the characters are 
created for the sake of the plot, and not the other way round. 
The plot must be a self-contained story with a clearly marked 
beginning, middle, and end; it must be sufficiently short and 
simple for the spectator to hold all its details in mind. Tragedy 
must have a unity. You do not make a tragedy by stringing 
together a set of episodes connected only by a common hero; 
rather, there must be a single significant action on which the 
whole plot turns (8. 1451a21—9).
In a typical tragedy the story gradually gets more complicated 
until a turning point is reached, which Aristotle calls a ‘reversal’ 
(peripeteia). That is the moment at which the apparently 
fortunate hero falls to disaster, perhaps through a ‘revelation’ 
(anagnorisis), namely his discovery of some crucial but hitherto 
unknown piece of information (15. 1454b19). After the reversal 
comes the denouement, in which the complications earlier 
introduced are gradually unravelled (18. 1455b24 ff.).
These observations are illustrated by constant reference to 
actual Greek plays, in particular to Sophocles’ tragedy King 
Oedipus. Oedipus, at the beginning of the play, enjoys 
p78rosperity and reputation. He is basically a good man, but has 
the fatal flaw of impetuosity. This vice makes him kill a stranger 
in a scuffle, and marry a bride without due diligence. The 
‘revelation’ that the man he killed was his father and the woman 
he married was his mother leads to the ‘reversal’ of his fortune, 
as he is banished from his kingdom and blinds himself in shame 
and remorse.
ARISTOTLE TO AUGUSTINE
Aristotle’s theory of tragedy enables him to respond to Plato’s 
complaint that playwrights, like other artists, were only imitators 
of everyday life, which was itself only an imitation of the real 
world of the Ideas. His answer is given when he compares drama 
with history.
From what has been said it is clear that the poet’s job is to 
describe not something that has actually happened, but 
something that might well happen, that is to say something that 
is possible because it is necessary or likely. The difference 
between a historian and a poet is not a matter of prose v. verse
—you might turn Herodotus into metre and it would still be 
history. It is rather in this matter of writing what happens rather 
than what might happen. For this reason poetry is more 
philosophical and more important than history; for poetry tells 
us of the universal, history tells us only of the particular. (9. 
1451b5—9)
What Aristotle says here of poetry and drama could of course 
be said of other kinds of creative writing. Much of what happens 
to people in everyday life is a matter of sheer accident; only in 
fiction can we see Athriest owtolerk’si nEgt hoicuat l oTfr ecahtaisraecster and action into 
their natural consequences.
If we turn from the productive sciences to the practical sciences, 
we find that Aristotle’s contribution was made by his writings on 
moral philosophy and political theory. Three treatises of moral 
philosophy have been handed down in the corpus: the 
Nicomachean Ethics (NE) in ten books, the Eudemian Ethics (EE) 
in seven books, and the Magna Moralia in two books. These texts 
are highly interesting to anyone who is interested in the 
development of Aristotle’s thought. Whereas in the physical and 
metaphysical treatises it is possible to detect traces of revision 
and rewriting, it is only in the case of ethics that we have 
Aristotle’s doctrine on the same topics presented in three 
diVerent and more or less complete courses. There is, however, 
no consensus on the explanation of this phenomenon.
In the early centuries after Aristotle’s death no great use was 
made of his ethical treatises by later writers; but the EE is more 
often cited than the NE, and the NE does not appear as such in 
the earliest catalogues of his Works. Indeed there are traces of 
some doubt whether the NE is a genuine work of Aristotle or 
perhaps a production of his son Nicomachus. However, 79
ARISTOTLE TO AUGUSTINE
from the time of the commentator Aspasius in the second 
century ad it has been almost universally agreed that the NE is 
not only genuine but also the most important of the three works. 
Throughout the Middle Ages, and since the revival of classical 
scholarship, it has been treated as the Ethics of Aristotle, and 
indeed the most generally popular of all his surviving works.
Very different views have been taken of the other works. While 
the NE has long appealed to a wide readership, the EE, even 
among Aristotelian scholars, has never appealed to more than a 
handful of fanatics. In the nineteenth century it was treated as 
spurious, and republished under the name of Aristotle’s pupil 
Eudemus of Rhodes. In the twentieth century scholars have 
commonly followed Werner Jaeger4 in regarding it as a genuine 
but immature work, superseded by an NE written in the Lyceum 
period. As for the Magna Moralia, some scholars followed Jaeger 
in rejecting it as post-Aristotelian, whereas others have argued 
hotly that it is a genuine work, the earliest of all three treatises.
There is a further problem about the relationship between the 
NE and the EE. In the manuscript tradition three books make a 
double appearance: once as books 5, 6, and 7 of the NE, and 
once as books 4, 5, and 6 of the EE. It is a mistake to try to settle 
the relationship between the NE and the EE without first 
deciding which was the original home of the common books. It 
can be shown on both philosophical and stylometric grounds 
that these books are much closer to the EE than to the NE. Once 
they are restored to the EE the case for regarding the EE as an 
immature and inferior work collapses: nothing remains, for 
example, of Jaeger’s argument that the EE is closer to Plato, and 
therefore earlier, than the NE. Moreover, internal historical 
allusions suggest that the disputed books, and therefore now the 
EE, belong to the Lyceum period.
There are problems concerning the coherence of the NE itself. At 
the beginning of the twentieth century the Aristotelian Thomas 
Case, in a celebrated article in the eleventh edition of the 
Encyclopaedia Britannica, suggested that ‘the probability is that 
the Nicomachean Ethics is a collection of separate discourses 
worked up into a tolerably systematic treatise.’ This remains 
highly probable. The differences between the NE and the EE do 
n80ot admit of a simple chronological solution: it may be that 
some of the discourses worked up into the NE antedate, and 
others postdate, the EE,
4 Aristotle: Fundamentals of the History of his Development, trans. R. 
Robinson (Oxford: Clarendon Press, 1948).
ARISTOTLE TO AUGUSTINE
which is itself a more coherent whole. The stylistic differences 
that separate the NE not only from the EE but also from almost 
all Aristotle’s other works may be explicable by the ancient 
tradition that the NE was edited by Nicomachus, while the EE, 
along with some of Aristotle’s other works, was edited by 
Eudemus. As for the Magna Moralia, while it follows closely the 
line of thought of the EE, it contains a number of 
misunderstandings of its doctrine. This is easily explained if it 
consists of notes made by a student at the Lyceum during 
Aristotle’s delivery of a course of lectures resembling the EE.5
The content of the three treatises is, in general, very similar. The 
NE covers much the same ground as Plato’s Republic, and with 
some exaggeration one could say that Aristotle’s moral 
philosophy is Plato’s moral philosophy with the Theory of Ideas 
ripped out. The Idea of the Good, Aristotle says, cannot be the 
supreme good of which ethics treats, if only because ethics is a 
practical science, about what is within human power to achieve, 
whereas an everlasting and unchanging Idea of the Good could 
only be of theoretical interest.
In place of the Idea of the Good, Aristotle offers happiness 
('eudaimonia) as the supreme good with which ethics is 
concerned, for, like Plato, he sees an intimate connection 
between living virtuously and living happily. In all the ethical 
treatises a happy life is a life of virtuous activity, and each of 
them offers an analysis of the concept of virtue and a 
classification of virtues of different types. One class is that of the 
moral virtues, such as courage, temperance, and liberality, that 
constantly appeared in Plato’s ethical discussions. The other 
class is that of intellectual virtues: here Aristotle makes a much 
sharper distinction than Plato ever did between the intellectual 
virtue of wisdom, which governs ethical behaviour, and the 
intellectual virtue of understanding, which is expressed in 
scientific endeavour and contemplation. The principal difference 
betwe5e n   th Teh Ne Ea cacnodu ntht eh eErEe  isg itvheant  oinf  the  rfoelramtieonr sAhriips tboetltew eregn atrhdes  
perfeAcrits tohtaepliapnin eetshsi caals t recaotnissetsit uist ecdo ntsroolveelyrs iabl.y  I thhaev e aecxtpivoiutnyd eodf  
and defended it in The Aristotelian Ethics (Oxford: Clarendon Press, 
philo1s9o7p8h) icaanld ,c ownitthe mcoprlraetcitoionn, sw ahnedr emaosd iinfi ctahteio nlas,t tienr  Aitr isctootnles iosnts t hoef  
the Phea6rf re m c tA oLrniifseito o(uOtlsxe f’ose rexdte:h rCicliaasrle t nedaocofh ni anPlgrle  issts he,e x1 p9lv9ai2irn)te.ude sin,  dienttaeill lienc Ctuha. l8  baenlodw .
moral.6
81
ARISTOTLE TO AUGUSTINE
Aristotle’s Political Theory
Even in the EE it is ‘the service and contemplation of God’ that 
sets the standard for the appropriate exercise of the moral 
virtues, and in the NE this contemplation is described as a 
superhuman activity of a divine part of ourselves. Aristotle’s final 
word here is that in spite of being mortal we must make 
ourselves immortal as far as we can. When we turn from the 
Ethics to their sequel, the Politics, we come down to earth. ‘Man 
is a political animal’, we are told: humans are creatures of flesh 
and blood, rubbing shoulders with each other in cities and 
communities.
Like his work in zoology, Aristotle’s political studies combine 
observation and theory. Diogenes Laertius tells us that he 
collected the constitutions of 158 states—no doubt aided by 
research assistants in the Lyceum. One of these, The 
Constitution of Athens, though not handed down as part of the 
Aristotelian corpus, was found on papyrus in 1891. In spite of 
some stylistic differences from other works, it is now generally 
regarded as authentic. In a codicil to the NE that reads like a 
preface to the Politics, Aristotle says that, having investigated 
previous writings on political theory, he will inquire, in the light 
of the constitutions collected, what makes good government and 
what makes bad government, what factors are favourable or 
unfavourable to the preservation of a constitution, and what 
constitution the best state should adopt (NE 10. 9. 1181b12—
23).
The Politics itself was probably not written at a single stretch, 
and here as elsewhere there is probably an overlap and 
interplay between the records of observation and the essays in 
theory. The structure of the book as we have it corresponds 
reasonably well to the NE programme: books 1—3 contain a 
general theory of the state, and a critique of earlier writers; 
books 4—6 contain an account of various forms of constitution, 
three tolerable (monarchy, aristocracy, polity) and three 
intolerable (tyranny, oligarchy, and democracy); books 7 and 8 
are devoted to the ideal form of constitution. Once again, the 
order of the discourses in the corpus probably differs from the 
order of their composition, but scholars have not reached 
82
agreement on the original chronology.
Aristotle begins by saying that the state is the highest kind of 
community, aiming at the highest of goods. The most primitive 
communities are families of men and women, masters and 
slaves. He seems to regard the
ARISTOTLE TO AUGUSTINE
division between master and slave as no less natural than the 
division between men and women, though he complains that it 
is barbaric to treat women and slaves alike (1. 2. 1252a25—b6). 
Families combine to make a village, and several villages 
combine to make a state, which is the first selfsufficient 
community, and is just as natural as is the family (1. 2. 1253a2). 
Indeed, though later than the family in time, the state is prior by 
nature, as an organic whole like the human body is prior to its 
organic parts like hands and feet. Without law and justice, man 
is the most savage of animals. Someone who cannot live in a 
state is a beast; someone who has no need of a state must be a 
god. The foundation of the state was the greatest of 
benefactions, because only within a state can human beings 
fulfil their potential (1. 2. 1253a25-35).
Among the earlier writers whom Aristotle cites and criticizes 
Plato is naturally prominent. Much of the second book of the 
Politics is devoted to criticism of the Republic and the Laws. As 
in the Ethics there is no Idea of the Good, so in the Politics there 
are no philosopher kings. Aristotle thinks that Platonic 
communism will bring nothing but trouble: the use
Aristotle saw women as inferior to men. Legend took revenge, as in 
this illustration to a text of Petrarch, showing him ridden and beaten by 
his wife, Phyllis.
83
ARISTOTLE TO AUGUSTINE
of property should be shared, but its ownership should be 
private. That way owners can take pride in their possessions and 
get pleasure out of sharing them with others or giving them 
away. Aristotle defends the traditional family against the 
proposal that women should be held in common, and he frowns 
even on the limited military and official role assigned to women 
in the Laws. Over and over again he describes Plato’s proposals 
as impractical; the root of his error, he thinks, is that he tries to 
make the state too uniform. The diversity of different kinds of 
citizen is essential, and life in a city should not be like life in a 
barracks (2. 3. 1261*10—31).
However, when Aristotle presents his own account of political 
constitutions he makes copious use of Platonic suggestions. 
There remains a constant difference between the two writers, 
namely that Aristotle makes frequent reference to concrete 
examples to illustrate his theoretical points. But the conceptual 
structure is often very similar. The following passage from book 
3, for instance, echoes the later books of the Republic.
The government, that is to say the supreme authority in a state, 
must be in the hands of one, or of a few, or of the many. The 
rightful true forms of government, therefore, are ones where the 
one, or the few, or the many, govern with a view to the common 
interest; governments that rule with a view to the private 
interest, whether of the one, or the few, or the many, are 
perversions. Those who belong to a state, if they are truly to be 
called citizens, must share in its benefits. Government by a 
single person, if it aims at the common interest, we are 
accustomed to call ‘monarchy’; similar government by a 
minority we call ‘aristocracy’, either because the rulers are the 
best men, or because it aims at the best interests of the state 
and the community. When it is the majority that governs in the 
common interest we call it a ‘polity’, using a word which is also a 
generic term for a constitution ... Of each of these forms of 
government there exists a perversion. The perversion of 
monarchy is tyranny; that of aristocracy is oligarchy; that of 
polity is democracy. For tyranny is a monarchy exercised solely 
for the benefit of the monarch, oligarchy has in view only the 
interests of the wealthy, and democracy the interests only of the 
poorer classes. None of these aims at the common good of all. 
(3. 6. 1279*26—b10)
Aristotle goes on to a detailed evaluation of constitutions of 
84
these various forms. He does so on the basis of his view of the 
essence of the state. A state, he tells us, is a society of humans 
sharing in a common perception of what is good and evil, just 
and unjust; its purpose is to provide a good and happy life for its 
citizens. If a community contains an individual or family of
ARISTOTLE TO AUGUSTINE
outstanding excellence, then monarchy is the best constitution. 
But such a case is very rare, and the risk of miscarriage is great: 
for monarchy corrupts into tyranny, which is the worst of all 
constitutions. Aristocracy, in theory, is the next best constitution 
after monarchy, but in practice Aristotle preferred a kind of 
constitutional democracy, for what he called ‘polity’ is a state in 
which rich and poor respect each others’ rights, and in which the 
best-qualified citizens rule with the consent of all the citizens (4. 
8. 1293b30 ff.). The corruption of this is what Aristotle calls 
‘democracy’, namely, anarchic mob rule. Bad as democracy is, it 
is in Aristotle’s view the least bad of the perverse forms of 
government.
At the present time we are familiar with the division of 
government into three branches: the legislature, the executive, 
and the judiciary. The essentials of this system is spelt out by 
Aristotle, though he distributes the powers in a somewhat 
different way from, say, the US constitution. All constitutions, he 
tells us, have three elements: the deliberative, the official, and 
the judicial. The deliberative element has authority in matters of 
war and peace, in making and unmaking alliances; it passes 
laws, controls the carrying out of judicial sentences, and audits 
the accounts of officers. The official element deals with the 
appointment of ministers and civil servants, ranging from priests 
through ambassadors to the regulators of female affairs. The 
judicial element consists of the courts of civil and criminal law 
(4. 12. 1296bl3—1301a12).
Two elements of Aristotle’s political teaching affected political 
institutions for many centuries: his justification of slavery and his 
condemnation of usury. Some people, Aristotle tells us, think 
that the rule of masters over slaves is contrary to nature, and is 
therefore unjust. They are quite wrong: a slave is someone who 
is by nature not his own but another man’s property. Slavery is 
one example of a general truth, that from their birth some 
people are marked out for rule and others to be ruled (1. 3. 
1253b20—3; 5. 1254b22-4).
In practice much slavery is unjust, Aristotle agrees. There is a 
custom that the spoils of war belong to the victors, and this 
includes the right to make slaves of the vanquished. But many 
wars are unjust, and victories in such wars entail no right 8t5o 
enslave the defeated. Some people, however, are so inferior and 
brutish that it is better for them to be under the rule of a kindly 
master than to be left to their own devices. Slaves, for Aristotle, 
are living tools—and on this basis he is willing to grant that if 
non-living tools
ARISTOTLE TO AUGUSTINE
could achieve the same purpose there would be no need for 
slavery. ‘If every instrument could achieve its own work, obeying 
or anticipating the will of others, like the statues of Daedalus ... 
if the shuttle could weave and the plectrum pluck the lyre in a 
similar manner, overseers would not need servants, nor masters 
slaves’ (1. 4. 1253b35—54a1). So perhaps, in an age of 
automation, Aristotle would no longer defend slavery.
Though not himself an aristocrat, Aristotle had an aristocratic 
disdain for commerce. Our possessions, he says, have two uses, 
proper and improper. The proper use of a shoe, for instance, is 
to wear it: to exchange it for other goods or for money is an 
improper use (1. 9. 1257a9—10). There is nothing wrong with 
basic barter for necessities, but there is nothing natural about 
trade in luxuries, as there is in farming. In the operation of retail 
trade money plays an important part, and money too has a 
proper and an improper use.
The most hated sort of wealth-getting is usury, which makes a 
profit out of money itself, rather than from its natural purpose, 
for money was intended to be used for exchange, not to 
increase at interest. It got the name ‘interest’ (tokos), which 
means the birth of money from money, because an offspring 
resembles its parent. For this reason, of all the modes of getting 
wealth this is the most unnatural. (1. 10. 1258b5—7)
Aristotle’s hierarchical preference places farmers at the top, 
bankers at the bottom, with merchants in between. His attitude 
to usury was one source of the prohibition, throughout medieval 
Christendom, of the charging of interest even at a modest rate. 
‘When did friendship’, Antonio asks Shylock in The Merchant of 
Venice, ‘take a breed for barren metal of his friend?’
One of the most striking features of Aristotle’s Politics is the 
almost total absence of any mention of Alexander or Macedon. 
Like a modern member of Amnesty International, Aristotle 
comments on the rights and wrongs of every country but his 
own. His own ideal state is described as having no more than a 
hundred thousand citizens, small enough for them all to know 
one another and to take their share in judicial and political 
office. It is very different from Alexander’s empire. When 
Aristotle says that monarchy is the best constitution if a 
c8o6mmunity contains a person or family of outstanding 
excellence, there is a pointed absence of reference to the royal 
family of Macedon.
Indeed, during the years of the Lyceum, relations between the 
world-conqueror and his former tutor seem to have cooled. 
Alexander became
ARISTOTLE TO AUGUSTINE
more and more megalomaniac and finally proclaimed himself 
divine. Aristotle’s nephew Callisthenes led the opposition to the 
king’s demand, in 327, that Greeks should prostrate themselves 
before him in adoration. He was falsely implicated in a plot, and 
executed. The magnanimous and magnificent man who is the 
hero of the earlier books of the NE has some of the grandiose 
traits of Alexander. In the EE, however, the alleged virtues of 
magnanimity and magnificence are downgraded, and gentleness 
and dignity take centre stage.7
Aristotle’s Cosmology
The greater part of Aristotle’s surviving works deal not with 
productive or practical sciences, but with the theoretical 
sciences. We have already considered his biological works: it is 
time to give some account of his physics and chemistry. His 
contributions to these disciplines were much less impressive 
than his researches in the life sciences. While his zoological 
writings were still found impressive by Darwin, his physics was 
superannuated by the sixth century ad.
In works such as On Generation and Corruption and On the 
Heavens Aristotle bequeathed to his successors a world-picture 
that included many features inherited from the Presocratics. He 
took over the four elements of Empedocles, earth, water, air, 
and fire, each characterized by the possession of a unique pair 
of the properties heat, cold, wetness, and dryness: earth being 
cold and dry, air being hot and wet, and so forth. Each element 
had its natural place in an ordered cosmos, and each element 
had an innate tendency to move towards this natural place. 
Thus, earthy solids naturally fell, while fire, unless prevented, 
rose ever higher. Each such motion was natural to its element; 
other motions were possible, but were ‘violent’. (We preserve a 
relic of Aristotle’s distinction when we contrast natural with 
violent death.)
In his physical treatises Aristotle offers explanations of an 
enormous number of natural phenomena in terms of the 
elements, their b7 aSseiec  mpyro Tphee rAtireissto, tealniadn  Etthheicisr,  2n3a3t.ural motion. The 
philosophical concepts which he employs in constructing these 
explanations include an array of different notions of causatio8n7 
(material, formal, efficient, and final), and an analysis
ARISTOTLE TO AUGUSTINE
of change as the passage from potentiality to actuality, whether 
(as in substantial change) from matter to form or (as in 
accidental change) from one to another quality of a substance. 
These technical notions, which he employed in such an 
astonishing variety of contexts, will be examined in detail in 
later chapters.
Aristotle’s vision of the cosmos owes much to his Presocratic 
precursors and to Plato’s Timaeus. The earth was in the centre 
of the universe: around it a succession of concentric crystalline 
spheres carried the moon, the sun, and the planets in their 
journeys around the visible sky. The heavenly bodies were not 
compounds of the four terrestrial elements, but were made of a 
superior fifth element or quintessence. They had souls as well as 
bodies: living supernatural intellects, guiding their travels 
through the cosmos. These intellects were movers which were 
themselves in motion, and behind them, Aristotle argued, there 
must be a source of movement not itself in motion. The only way 
in which an unchanging, eternal mover could cause motion in 
other beings was by attracting them as an object of love, an 
attraction which they express by their perfect circular motion. It 
is thus that Dante, in the final lines of his Paradiso, finds his own 
will, like a smoothly rotating wheel, caught up in the love that 
moves the sun and all the other stars.
Even the best of Aristotle’s scientific work has now only a 
historical interest. The abiding value of treatises such as his 
Physics is in the philosophical analyses of some of the basic 
concepts that pervade the physics of different eras, such as 
space, time, causation, and determinism. These are examined in 
detail in Chapter 5. For Aristotle biology and psychology were 
parts of natural philosophy no less than physics and chemistry, 
since they too studied different forms ofphysis, or nature. The 
biological works we have already looked at; the psychological 
works will be examined more closely in Chapter 7.
The Aristotelian corpus, in addition to the systematic scientific 
treatises, contains a massive collection of occasional jottings on 
scientific topics, the Problems. From its structure this appears to 
be a commonplace book in which Aristotle wrote down 
provisional answers to questions that were put to him by his 
s8t8udents or correspondents. Because the questions are grouped 
rather haphazardly, and often appear several times—and are 
sometimes given different answers—it seems unlikely that they 
were generated by Aristotle himself, whether as a single series 
or over a lifetime.
ARISTOTLE TO AUGUSTINE
But the collection contains many fascinating details that throw 
insight into the workings of his omnivorous intellect.
Some of the questions are the kind of thing a patient might 
bring to a doctor. Ought drugs to be used, rather than surgery, 
for sores in the armpits and groin? (1. 34. 863a21). Is it true that 
purslane mixed with salt stops inflammation of the gums? (1. 
38. 863b12). Does cabbage really cure a hangover? (3. 17. 
873b1). Why is it difficult to have sex under water? (4. 14. 
878a35). Other questions and answers make us see Aristotle 
more in the role of agony aunt. How should one cope with the 
after-effects of eating garlic? (13. 2. 907b28—908a10). How does 
one prevent biscuit from becoming hard? (21. 12. 928a12). Why 
do drunken men kiss old women they would never kiss when 
sober? (30. 15. 953bffi). Is it right to punish more seriously 
thefts from a public place than thefts from a private house? (29. 
14. 952affi). More seriously, why is it more terrible to kill a 
woman than a man, although the male is naturally superior to 
the female? (29. 11. 95U12).
A whole book of the Problems (26) is devoted essentially to 
weather forecasting. Other books contain questions that simply 
reflect general curiosity. Why does the noise of a saw being 
sharpened set our teeth on edge? (7. 5. 886bffi). Why do 
humans not have manes? (10. 25. 893b17). Why do non-human 
animals not sneeze or squint? (Don’t they?) (10. 50. 896b5; 54. 
897a1). Why do barbarians and Greeks alike count up to ten? 
(15. 3. 9^23). Why is a flute better than a lyre as an 
accompaniment to a solo voice? (19. 43. 922a1). Very often, the 
Problems ask ‘Why is such and such the case?’ when a more 
appropriate question would have been ‘Is such and such the 
case?’ For instance, Why do fishermen have red hair? (37. 2. 
966b25). Why does a large choir keep time better than a small 
one? (19. 22. 9^36).
The Problems let us see Aristotle with his hair down, rather like 
the table talk ofT lhatee Lr ewgraitceyr so.f  OAnries tooft lhei sa nqdu ePslatitoons is particularly 
endearing to those who may have found it hard to read their 
When Alexander the Great died in 323, democratic Athens 
way through his more difficult works: Why is it that some 
became uncomfortable even for an anti-imperialist Macedonian. 
people, if they begin to read a serious book, are overcome by 
Saying that he did not
sleep even against their will? (18. 1. 9^1).
89
ARISTOTLE TO AUGUSTINE
wish the city that had executed Socrates ‘to sin twice against 
philosophy’, Aristotle escaped to Chalcis, where he died in the 
following year. His will, which survives, makes thoughtful 
provision for a large number of friends and dependants. His 
library was left to Theophrastus, his successor as head of the 
Lyceum. His own papers were vast in size and scope—those that 
survive today total around a million words, and it is said that we 
possess only one-fifth of his output. As we have seen, in addition 
to philosophical treatises on logic, metaphysics, ethics, 
aesthetics, and politics, they included historical works on 
constitutions, theatre and sport, and scientific works on botany, 
zoology, biology, psychology, chemistry, meteorology, 
astronomy, and cosmology.
Since the Renaissance it has been traditional to regard the 
Academy and the Lyceum as two opposite poles of philosophy. 
Plato, according to this tradition, was idealistic, utopian, other-
worldly; Aristotle was realistic, utilitarian, commonsensical. 
Thus, in Raphael’s School of Athens Plato, wearing the colours of 
the volatile elements air and fire, points heavenwards; Aristotle, 
clothed in watery blue and earthy green, has his feet firmly on 
the ground. ‘Every man is born an Aristotelian or a Platonist,’ 
wrote S. T. Coleridge. ‘They are the two classes of men, besides 
which it is next to impossible to conceive a third.’ The 
philosopher Gilbert Ryle in the twentieth century improved on 
Coleridge. Men could be divided into two classes on the basis of 
four dichotomies: green versus blue, sweet versus savoury, cats 
versus dogs, Plato versus Aristotle. ‘Tell me your preference on 
one of these pairs’, Ryle used to say, ‘and I will tell you your 
preference on the other three.’8
In fact, as we have already seen and will see in greater detail 
later, the doctrines that Plato and Aristotle share are more 
important than those that divide them. Many post-Renaissance 
historians of ideas have been less perceptive than the many 
commentators in late antiquity who saw it as their duty to 
construct a harmonious concord between the two greatest 
philosophers of the ancient world.
It is sometimes said that a philosopher should be judged by the 
importance of the questions he raises, not the correctness of the 
a90nswers he gives. If that is so, then Plato has an uncontestable 
claim to pre-eminence as a philosopher. He was the first to pose 
questions of great profundity, many of
8 Preference for an item on the left of a pair was supposed to go with 
preference for the other leftward items, and similarly for rightward 
preferences.
ARISTOTLE TO AUGUSTINE
which remain open questions in philosophy today. But Aristotle 
too can claim a significant contribution to the intellectual 
patrimony of the world. For it was he who invented the concept 
of Science as we understand it today and as it has been 
understood since the Renaissance.
First, he is the first person whose surviving works show detailed 
observations of natural phenomena. Secondly, he was the first 
philosopher to have a sound grasp of the relationship between 
observation and theory in scientific method. Thirdly, he 
identified and classified different scientific disciplines and 
explored their relationships to each other: the very concept of a 
distinct discipline is due to him. Fourthly, he is the first professor 
to have organized his lectures into courses, and to have taken 
trouble over their appropriate place in a syllabus (cf. Pol. 1. 10. 
1258a20). Fifthly, his Lyceum was the first research institute of 
which we have any detailed knowledge in which a number of 
scholars and investigators joined in collaborative inquiry and 
documentation. Sixthly, and not least important, he was the first 
person in history to build up a research library—not simply a 
handful of books for his own bookshelf, but a systematic 
collection to be used by his colleagues and to be handed on to 
posterity.9 For all these reasons, every academic scientist in the 
world today is in Aristotle’s debt. He well deserved the title he 
was given by Dante: ‘theA rmisatostteler’ so fS tchhoosoel who know’.
Theophrastus (372—287), Aristotle’s ingenious successor as 
head of the Lyceum, continued his master’s researches in 
several ways. He wrote extensively on botany, a discipline that 
Aristotle had touched only lightly. He improved on Aristotle’s 
modal logic, and anticipated some later Stoic innovations. He 
disagreed with some fundamental principles of Aristotle’s 
cosmology, such as the nature of place and the need for a 
motionless mover. Like his master, he wrote copiously, and the 
mere list of the titles of his works takes up sixteen pages in the 
Loeb edition of his life by Diogenes Laertius. They include essays 
on vertigo, on honey, on hair, on jokes, and on the eruption of 
Etna. T9h See eb eL.s tC aksnsoown,n L iobfr ahriiess s inu rthveiv Ainncgie wnto Wrkosrl dis ( Nae bwo Hokaven: Yale University Press, 2001), 28—9.
91
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