Frank Plumpton Ramsey - Foundations of Mathematics and Other Logical Essays

The International Library of Philosophy

PHILOSOPHY OF LOGIC AND MATHEMATICS

In 8 Volumes

First published in 1931 by
Routledge

Reprinted in 2000, 2001 (twice) by
Routledge
2 Park Square, Milton Park, Abingdon, Oxon, OX14 4RN

Transferred to Digital Printing 2006

Routledge is an imprint of the Taylor & Francis Group

1931 Editorial Selection and Introduction R. B. Braithwaite

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British Library Cataloguing in Publication Data
A CIP catalogue record for this book is available from the British Library

The Foundations of Mathematics
ISBN 0-415-22546-9
Philosophy of Logic and Mathematics: 8 Volumes
ISBN 0-415-22575-2
The International Library of Philosophy: 56 Volumes
ISBN 0-415-21803-9

ISBN10: 0-415-22546-9 (hbk)
ISBN10: 0-415-40852-0 (pbk)

ISBN13: 978-0-415-22546-5 (hbk)
ISBN13: 978-0-415-40852-3 (pbk)

eISBN: 978-1-134-52810-3

Published Papers

Unpublished Papers

T HE author of the papers collected in this volume seemed to me to combine very exceptional brilliance with very great soundness of judgment in philosophy. He was an extraordinarily clear thinker: no-one could avoid more easily than he the sort of confusions of thought to which even the best philosophers are liable, and he was capable of apprehending clearly, and observing consistently, the subtlest distinctions. He had, moreover, an exceptional power of drawing conclusions from a complicated set of facts: he could see what followed from them all taken together, or at least what might follow, in cases where others could draw no conclusions whatever. And, with all this, he produced the impression of also possessing the soundest common sense: his subtlety and ingenuity did not lead him, as it seems to have led some philosophers, to deny obvious facts. He had, moreover, so it seemed to me, an excellent sense of proportion: he could see which problems were the most fundamental, and it was these in which he was most interested and which he was most anxious to solve. For all these reasons, and perhaps for others as well, I almost always felt, with regard to any subject which we discussed, that he understood it much better than I did, and where (as was often the case) he failed to convince me, I generally thought the probability was that he was right and I wrong, and that my failure to agree with him was due to lack of mental power on my part.

Ramsey was not only exceptionally capable of thinking clearly himself; he also had a most uncommon power of explaining clearly to others what he thought and why he thought it. There are many good examples in this volume of his great capacity for lucid exposition. But sometimes I feel that he fails to explain things as clearly as he could have done, simply because he does not see that any explanation is needed: he does not realize that what to him seems perfectly clear and straightforward may to others, less gifted, offer many puzzles. I must confess that I personally often find a difficulty in understanding at all clearly what he means, in cases where he does not seem to have been aware than any difficulty whatever would be found. No doubt, in many of these cases, some readers will understand him without difficulty; but I suspect that many will be in my case. In the last two sections of the volume (the notes of 1928 and 1929), where he was writing chiefly for himself and not expanding and explaining as he would have done if writing for publication, the difficulty of following him with adequate comprehension is naturally specially great. But even where you cannot understand him completely you can often understand him enough to find him extraordinarily interesting; and I am convinced that it is well worth while to try to understand him. No doubt sometimes he may make mere mistakes; but in general I think he himself knew very well indeed what he was about, and, even if he was wrong, had very good reasons for the opinions at which he had arrived. It is a great misfortune that his early death prevented him from making these opinions, and the reasons for them, as clear as he, and perhaps he alone, could have made them.

G. E. MOORE.

December. 1930.

FRANK PLUMPTON RAMSEY was born on 22nd February, 1903, and died on 19th January, 1930. The son of the President of Magdalene, he spent nearly all his life in Cambridge, where he was successively Scholar of Trinity, Fellow of Kings, and Lecturer in Mathematics in the University. His death at the height of his powers deprives Cambridge of one of its intellectual glories and contemporary philosophy of one of its profoundest thinkers.

Though mathematical teaching was Ramseys profession, philosophy was his vocation. Reared on the logic of Principia Mathematica, he was early to see the importance of Dr. Wittgensteins work (in the translation of which he assisted); and his own published papers were largely based on this. But the previously unprinted essays and notes collected in this volume show him moving towards a kind of pragmatism, and the general treatise on logic upon which at various times he had been engaged was to have treated truth and knowledge as purely natural phenomena to be explained psychologically without recourse to distinctively logical relations. Ramseys philosophy, however, was always tentative and experimentalhis calmness in infanticide frequently amazed his friendsand the papers in this volume are published as important in themselves and as likely to lead to work on similar lines and not as the exposition of a consistent and complete philosophical system.

The subtlety and fertility of Ramseys philosophical work as shown here need no advertisement; but since his two papers on mathematical economics are not included, I have obtained Mr. J. M. Keynes permission to quote from his notice in