Roger Penrose - The Emperor’s New Mind: Concerning Computers, Minds, and the Laws of Physics

THE EMPERORS NEW MIND

Roger Penrose is the Emeritus Rouse Ball Professor of Mathematics at the University of Oxford and Gresham Professor of Geometry, Gresham College, London. He has a part-time appointment as Francis and Helen Pentz Distinguished Professor of Physics and Mathematics, Penn State University, USA. Born in Colchester, Essex, in 1931, he attended University College School, London, was awarded a B.Sc. degree at University College London and a Ph.D. at St Johns College, Cambridge. He has held several posts in the UK and USA, most particularly at Birkbeck College, London. He was elected a Fellow of the Royal Society of London in 1972 and a Foreign Associate of the United States National Academy of Sciences in 1998. He has received a number of prizes and awards including the 1988 Wolf Prize, which he shared with Stephen Hawking for their understanding of the universe, the Dannie Heinemann Prize, the Royal Society Royal Medal, the Dirac Medal, and the Albert Einstein prize. His 1989 book The Emperors New Mind became a bestseller and won the 1990 (now Rhne-Poulenc) Science Book Prize. His latest books are Shadows of the Mind (1994), The Nature of Space and Time (1996) with Stephen Hawking, and The Large, the Small and the Human Mind (1997).

He has research interests in many aspects of geometry, having made contributions to the theory of non-periodic tilings, to general relativity theory, and the foundations of quantum theory. He has contributed to the science of consciousness. His main research programme is to develop the theory of twistors, which he originated over thirty years ago as an attempt to unite Einsteins general theory of relativity with quantum mechanics. He was knighted in 1994 for services to science.

Other books by Roger Penrose

Shadows of the Mind The
Large, the Small and the Human Mind

With Stephen Hawking
The Nature of Space and Time

With Wolfgang Rindler
Spinors and Space-Time, Vols. 1 and 2

Roger Penrose

Concerning Computers, Minds and The Laws of Physics

FOREWORD BY
Martin Gardner

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Oxford University Press 1989
Preface Roger Penrose 1999

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First published 1989
First published as an Oxford University Press paperback with a new preface 1999

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ISBN-13: 978-0-19-286198-6
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on acid-free paper by
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DEDICATION

I dedicate this book to the loving memory of my dear mother, who did not quite live to see it.

AT A NUMBER of places in this book I have resorted to the use of mathematical formulae, unabashed and unheeding of warnings that are frequently given: that each such formula will cut down the general readership by half. If you are a reader who finds any formula intimidating (and most people do), then I recommend a procedure that I normally adopt myself when such an offending line presents itself. The procedure is, more or less, to ignore that line completely and to skip over to the next actual line of text! Well, not exactly this; one should spare the poor formula a perusing, rather than a comprehending glance, and then press onwards. After a little, if armed with new confidence, one may return to that neglected formula and try to pick out some salient features. The text itself may be helpful in letting one know what is important and what can be safely ignored about it. If not, then do not be afraid to leave a formula behind altogether.

THERE ARE MANY who have helped me, in one way or another, in the writing of this book, and to whom thanks are due. In particular, there are those proponents of strong AI (especially those who were involved in a BBC TV programme I once watched) who, by the expressions of such extreme AI opinions, had goaded me, a number of years ago, into embarking upon this project. (Yet, had I known of the future labours that the writing would involve me in, I fear, now, that I should not have started!) Many people have perused versions of small parts of the manuscript and have provided me with many helpful suggestions for improvement; and to them, I also offer my thanks: Toby Bailey, David Deutsch (who was also greatly helpful in checking my Turing machine specifications), Stuart Hampshire, Jim Hartle, Lane Hughston, Angus Mclntyre, Mary Jane Mowat, Tristan Needham, Ted Newman, Eric Penrose, Toby Penrose, Wolfgang Rindler, Engelbert Schcking, and Dennis Sciama. Christopher Penroses help with detailed information concerning the Mandelbrot set is especially appreciated, as is that of Jonathan Penrose, for his useful information concerning chess computers. Special thanks go to Colin Blakemore, Erich Harth, and David Hubel for reading and checking over on quantum mechanics took place). I am greatly indebted, also, to Martin Gardner for his extreme generosity in providing the foreword to this work, and also for some specific comments. Most particularly, I thank my beloved Vanessa, for her careful and detailed criticism of several chapters, for much invaluable assistance with references and, by no means least, for putting up with me when I have been at my most insufferable and for her deep love and support where it was vitally needed.

THE PUBLISHERS EITHER have sought or are grateful to the following for permission to reproduce illustration material.

from D. A. Klarner (ed.), The mathematical Gardner (Wadsworth International, 1981).

from B. Grnbaum and G. C. Shephard, Tilings and patterns (W. H. Freeman, 1987). Copyright 1987 by W. H. Freeman and Company. Used by permission.

from K. Chandrasekharan,