Table Of ContentAN INTRODUCTION TO THE PHILOSOPHY
OF KNOWLEDGE
Also by Jennifer Trusted
INQUIRY AND UNDERSTANDING
THE LOGIC OF SCIENTIFIC INFERENCE
FREE WILL AND RESPONSIBILITY
MORAL PRINCIPLES AND SOCIAL VALUES
PHYSICS AND METAPHYSICS
BELIEFS AND BIOLOGY
An Introduction to the
Philosophy of Knowledge
Jennifer Trusted
Second Edition
* © Jennifer Trusted 1981, 1997
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PAlGRAVE is the new global academic imprint of
5t. Martin's Press llC Scholarly and Reference Division and
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First edition 1981
Second edition 1997
ISBN 978-0-333-69186-1 ISBN 978-0-230-37824-7 (eBook)
DOI10.1057/9780230378247
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Contents
Acknowledgements vi
Preface vii
1 The Nature of Philosophy 1
2 Plato's View of Knowledge 25
3 Aristotle's View of Knowledge 48
4 Descartes - the Quest for Certainty 66
5 Descartes - the Cogito 90
6 The British Empiricists: Locke and Berkeley 109
7 Hume's Reappraisal and his Problem 147
8 Kant's Attempt to Solve Hume's Problem 178
9 Knowledge and Perception 200
10 Knowledge and Belief 230
11 Some Conclusions 253
Glossary 261
Bibliography 266
Index 268
Acknowledgements
I should like to thank Professor O'Connor and Professor
Atkinson for their very great help and encouragement. I
should also like to thank Professor Ayer for commenting on
chapters 7, 8 and 9. Any mistakes in the text are, of course,
my own.
J. T.
The author and publishers wish to thank the following who have
kindly given permission for the use of copyright material:
Professor Sir A. J. Ayer for extracts from T7le Problem oj Knowledge;
Basil Blackwell Publisher Limited for an abridged version of
Knowledge and Beliefby Norman Malcolm originally published in full
in Mind, 51 (1952); Dr G. D. Chryssides for a winning entry in a
competition published in T7le Times Higher Education Supplement;
Faber & Faber Limited and Mrs Valerie Eliot for a letter to T7le
Times, 10 February 1970; Manchester University Press for extracts
from Immanual Kant: Prolegomena (Philosophical Classics Series) trans.
by P. G. Lucas; The New American Library Inc. for extracts from
Great Dialogues oj Plato, trans. by W. H. D. Rouse and ed. by Philip
G. Rouse and Eric H. Warmington, Copyright © 1956, 1961 by
John Clive Graves Rouse; Thomas Nelson & Sons Limited for
extracts from Rene Descartes: Philosophical Writings, trans. by E.
Anscombe and P. T. Geach; Oxford University Press for selections
from Sense and Sensibilia by J. L. Austin, ed. by G. J. Warnock, ©
1962; from T7le Oiford Translation oj Aristotle, ed. by W. D. Ross;
from T7le Problems oj Philosophy by Bertrand Russell (1912), and from
T7le Oiford Book oj Literary Anecdotes (pp. 242-3) ed. by James
Sutherland (1975); Thames and Hudson Limited for extracts from
An Introduction to Western Philosophy, by A. Flew; Weidenfeld &
Nicolson Limited for extracts from The Central Qjlestions oj Philosophy,
by A.J. Ayer.
Preface
The object of this book is to provide an introduction to
philosophy for students; but it is also intended for the educa
ted general reader who wishes to learn something of the
nature of the subject.
Apart from Descartes and Kant, all the later philosophers
discussed wrote in English but, even with this restriction, it is
hoped that the general reader will find the book interesting,
and will find it useful in bringing about an appreciation of
essentially philosophical discussion and analysis.
For though a very large number of intelligent and alert
people are attracted to philosophy, many of them have a very
confused idea as to its nature. This is because philosophy is a
subject which differs from all other subjects in that its aims
and techniques are its content. Other subjects have their
philosophies: philosophy of science, philosophy of history
etc. and these philosophies may be appreciated with minimal
knowledge of the content of the subjects. Certainly one can
know something of the general aims and assumptions, and
even something of the methods of the natural sciences, of
history, of law, of the various arts without being a scientist, a
historian, a lawyer, a musician or a painter. But the general
aims, assumptions and methods of philosophy are themselves
part of philosophy, and so one cannot know them without
being a philosopher. That is why ignorance of the content of
philosophy involves ignorance of the nature of philosophy -
they are inseparable.
There are many books offering good elementary accounts
of philosophy, of philosophers and of particular philosophical
problems. These three topics cannot be distinguished as easily
Vlll PREFACE
as can their analogues in other subjects. But, of course, there
are degrees of emphasis. The author may give asimple account
of certain philosophical problems as does Bertrand Russell in
The Problems of Philosophy, or he or she may provide a
historical picture of the work of many different philosophers,
as Russell does in his History of J.testern Philosophy. A more
detailed, though for that very reason a less comprehensive,
historical account is given in A Critical History of J.testern
Philosophy edited by D. J. 0 'Connor. This provides a more
scholarly account than does Russell in his History, because
different specialist writers can give a deeper and more critical
assessment than can anyone individual. At a more advanced
level, A. J. Ayer presents a modern analysis of a wide range
of philosophical problems in his Central Questions of Philosophy.
This book is similar in some respects to Russell's Problems of
Philosophy, and indeed comparison with Russell's book is
invited, but it is more detailed and, as well as referring to
works which had not appeared in Russell's day, it requires
some philosophical background knowledge to be appreciated.
Another approach to presenting elementary philosophy is
shown by Antony Flew in An Introduction to J.testern Philosophy.
Flew takes various philosophical themes and draws the
attention of the reader to their treatment by different
philosophers. There are long quotations from many different
sources, and Flew provides comment and connection between
the various writers and various themes.
Later works which appeared after my first edition went to
press are The History of Scepticism by Richard H. Popkin,
Rationalism by John Cottingham, Modern Philosophy by Roger
Scruton and Philosophy: the Basics by Nigel Warburton. Popkin
provides a historical background to the development of
contemporary critical analysis but ends his account with
Spinoza; his presentation does require some background
knowledge to be fully appreciated. Cottingham's book is
written for the general reader as well as for students and his
account extends from Plato to Popper. His final chapter treats
of falsifiability and current approaches in the philosophy of
science. Scruton's book covers a wider range of topics. Those
interested in philosophy of knowledge would find chapters I
and 2 and chapters 22 and 23 particularly interesting.
PREFACE IX
Scruton implies that his text is accessible to the general
reader but it is densely, though clearly, argued and those with
no prior knowledge would probably find it difficult. By
contrast Warburton's book is eminently readable and gives a
lucid account of the nature of philosophy. A second, and
slightly expanded, edition was published in 1995.
The approach here has something in common with all the
books mentioned. Firstly, like all of them, it is an
introduction to Western philosophy and, as already indicated,
to Western philosophy as it is taught in many universities,
that is with a marked bias towards an empiricist tradition.
Secondly the treatment is historical as is the treatment in
O'Connor, Flew, Russell, Popkin, Cottingham and (to a lesser
extent) Russell, Scruton and Warburton. Thirdly, it is similar
to Flew's book, though not to the others, in that there are
very substantial quotations and a considerable portion of the
text is devoted to quotation and comment. Where it differs
from all these books, save for Warburton's, is that it is written
as a basis for further study. The book is self-contained but it is
meant to provide a foundation for students as well as being a
text for the general reader.
It is for this reason that the theme is very much restricted,
far more restricted than in the other books. The theme is
epistemology and, in particular, the emergence of the distinc
tion between the nature of the evidence required to justify a
claim to empirical knowledge, as opposed to a claim to
logical knowledge. I hope that the text allows the reader to
appreciate how the notion of empirical knowledge as
something having a different status from logical knowledge,
gradually established itself; and how the quest for certainty
about the nature of the empirical world had to be abandoned
and replaced by a quest for understanding.
It seems to me that this theme is particularly well suited to
historical treatment, for all philosophers have been con
cerned with knowledge, and the works of early writers are
still influential and therefore still important today. In nine of
the chapters of the book it is just nine philosophers whose
works are discussed at any length. The selection is unlikely to
surprise any teacher of philosophy, but it is inevitable that
none of the philosophers considered can be fully discussed
