The Sleepwalkers
A history of man's changing vision of the Universe
ARTHUR KOESTLER
With an Introduction by
HERBERT BUTTERFIELD, M.A.
Master of Peterhouse and Professor of Modern History
in the University of Cambridge
New York
THE MACMILLAN COMPANY* 1959
CONTENTS
Introduction
Preface
PART ONE THE HEROIC AGE
I DAWN
1. Awakening. 2. Ionian Fever.
II THE HARMONY OF THE SPHERES
1. Pythagoras of Samos. 2. The Unifying Vision. 3. "Soft Stillness and the Night." 4. Religion and Science Meet. 5. Tragedy and Greatness of the Pythagoreans.
III THE EARTH ADRIFT
1. Philolaus and the Central Fire. 2. Herakleides and the Sun-Centred Universe. 3. Aristarchus, the Greek Copernicus.
IV THE FAILURE OF NERVE
1. Plato and Aristotle. 2. Rise of the Circular Dogma. 3. The Fear of Change
V THE DIVORCE FROM REALITY
1. Spheres Within Spheres (Eudoxus). 2. Wheels Within Wheels: (Ptolemy). 3. The Paradox. 4. Knowing and Un-Knowing. 5. The New Mythology. 6. The Cubist Universe.
Chronological Table to Part One
PART TWO DARK INTERLUDE
I THE RECTANGULAR UNIVERSE
1. The City of God. 2. The Bridge to the City. 3. The Earth as a Tabernacle. 4. The Earth is Round Again.
II THE WALLED-IN UNIVERSE
1. The Scale of Being. 2. The Age of Double-Think.
III THE UNIVERSE OF THE SCHOOLMEN
1. The Thaw. 2. Potency and Act. 3. The Weeds. 4. Summary.
Chronological Table to Part Two
PART THREE THE TIMID CANON
I THE LIFE OF COPERNICUS
1. The Mystifier. 2. Uncle Laws. 3. The Student. 4. Brother Andreas. 5. The Secretary. 6. The Canon. 7. The Commentariolus. 8. Rumour and Report. 9. The Arrival of Rheticus. 10. Narratio Prima. 11. Preparations for the Printing. 12. The Scandal of the Preface. 13. The Betrayal of Rheticus. 14. Bishop Dantiscus. 15. Death of Copernicus. 16. Death of Rheticus.
II THE SYSTEM OF COPERNICUS
1. The Book That Nobody Read. 2. The Arguments for the Earth's Motion. 3. The Last of the Aristotelians. 4. Genesis of the System. 5. The First Repercussions. 6. The Delayed Effect.
Chronological Table to Part Three
PART FOUR THE WATERSHED
I THE YOUNG KEPLER
1. Decline of a Family. 2 Job. 3. Orphic Purge. 4. Appointment. 5. Astrology.
II THE "COSMIC MYSTERY"
1. The Perfect Solids. 2. Contents of the Mysterium. 3. Back to Pythagoras.
III GROWING PAINS
1. The Cosmic Cup. 2. Marriage. 3. Limbering Up. 4. Waiting for Tycho.
IV TYCHO DE BRAHE
1.The Quest for Precision. 2. The New Star. 3. Uraniburg. 4. Exile. 5. Prelude to the Meeting.
V TYCHO AND KEPLER
1. The Gravity of Fate. 2. The Inheritor.
VI THE GIVING OF THE LAWS
1. Astronomia Nova. 2. Opening Gambits. 3. The First Assault. 4. The Eight Minutes Arc. 5. The Wrong Law. 6. The Second Law. 7. The First Law. 8. Some Conclusions. 9. The Pitfalls of Gravity. 10. Matter and Mind
VII KEPLER DEPRESSED
I. Publishing Difficulties. 2. Reception of Astronomia Nova. 3. Anticlimax. 4. The Great News.
VIII KEPLER AND GALILEO
1. A Digression on Mythography. 2. Youth of Galileo. 3. The Church and the Copernican System. 4. Early Quarrels. 5. The Impact of the Telescope. 6. The Battle of the Satellites. 7. The Shield Bearer. 8. The Parting of the Orbits.
IX CHAOS AND HARMONY
1. Dioptrice. 2. Disaster. 3. Excommunication. 4. The Witch Trial. 5. Harmonice Mundi. 6. The Third Law. 7. The Ultimate Paradox.
X COMPUTING A BRIDE
XI THE LAST YEARS
1. Tabulae Rudolphinae. 2. The Tension Snaps. 3. Wallenstein. 4. Lunar Nightmare. 5. The End.
PART FIVE THE PARTING OF THE WAYS
I THE BURDEN OF PROOF
1. Galileo's Triumph. 2. The Sunspots. 3. The Shifting of the Burden. 4. The Denunciation. 5. The Refusal to Compromise. 6. The "Secret Weapon". 7. The Decree of the Holy Office. 8. The Injunction.
II THE TRIAL OF GALILEO
1. The Tides. 2. The Comets. 3. Dangerous Adulation. 4. The Dialogue. 5. The Imprimatur. 6. The Trial.
III THE NEWTONIAN SYNTHESIS
1. 'Tis all in Pieces. 2. What is "Weight"? 3. The Magnetic Confusion. 4. Enter Gravity. 5. The Final Synthesis.
Chronological Table to Parts Four and Five
EPILOGUE
1. The Pitfalls of Mental Evolution. 2. Separations and Reintegrations. 3. Some Patterns of Discovery. 4. Mystic and Savant. 5. The Fatal Estrangement. 6. The Vanishing Act. 7. The Conservatism of Modern Science. 8. From Hierarchy to Continuum. 9. The Ultimate Decision.
Notes
Selected Bibliography
Index
INTRODUCTION
No field of thought can be properly laid out by men who are merely measuring with a ruler. Sections of history are liable to be transformed – or, even where not transformed, greatly vivified – by an imagination that comes, sweeping like a searchlight, from outside the historical profession itself. Old hunches are then confirmed by fresh applications of the evidence or by unexpected correlations between sources. New matter emerges because things are joined together which it had not occurred to one to see in juxtaposition. New details are elicited, difficult details become relevant, because of a fresh turn that the argument has taken.
We are constantly finding that we have been reading too much modernity into a man like Copernicus, or have merely been selecting from Kepler (and plucking out of their context) certain things which have a modern ring; or, in a similar manner, we have been anachronistic in our treatment of the mind and life of Galileo. The present author carries this particular process further, picks up many loose ends, and gives the whole subject a number of unexpected ramifications. Looking not only at the scientific achievements but at the working-methods behind them, and at a good deal of private correspondence, he has illuminated great thinkers, putting them back into their age, and yet not making them meaningless – not leaving us with anomalies and odds-and-ends of antiquated thought, but tracing the unity, recovering the texture and showing us the plausibility and the self-consistency of the underlying mind.
It is particularly useful for English readers that Mr. Koestler has concentrated on some of the aspects of the story that have been neglected, and has paid great attention to Kepler, who most required exposition and most called for historical imagination. History is not to be judged by negatives; and those of us who differ from Mr. Koestler in respect of some of the outer frame-work of his ideas or who do not follow him in certain details, can hardly fail to catch the light which not only modifies and enlivens the picture but brings out new facts, or makes dead ones dance before our eyes.
It will be surprising if even those who are familiar with this subject do not often feel that here is a shower of rain where every drop has caught a gleam.
HERBERT BUTTERFIELD
PREFACE
IN the index to the six hundred odd pages of Arnold Toynbee's A Study of History, abridged version, the names of Copernicus, Galileo, Descartes and Newton do not occur. 1 This one example among many should be sufficient to indicate the gulf that still separates the Humanities from the Philosophy of Nature. I use this outmoded expression because the term "Science", which has come to replace it in more recent times, does not carry the same rich and universal associations which "Natural Philoso
phy" carried in the seventeenth century, in the days when Kepler wrote his Harmony of the World and Galileo his Message from the Stars. Those men who created the upheaval which we now call the "Scientific Revolution" called it by a quite different name: the "New Philosophy". The revolution in technology which their discoveries triggered off was an unexpected by-product; their aim was not the conquest of Nature, but the understanding of Nature. Yet their cosmic quest destroyed the mediaeval vision of an immutable social order in a walled-in universe together with its fixed hierarchy of moral values, and transformed the European landscape, society, culture, habits and general outlook, as thoroughly as if a new species had arisen on this planet.
This mutation of the European mind in the seventeenth century is merely the latest example of the impact of the "Sciences" on the "Humanities" – of the inquiry into the nature of Nature on the inquiry into the nature of Man. It also illustrates the wrongheadedness of erecting academic and social barriers between the two; a fact which is at last beginning to gain recognition, nearly half a millennium after the Renaissance discovered the uomo universale.
Another result of this fragmentation is that there exist Histories of Science, which tell one at what date the mechanical clock or the law of inertia made their first appearance, and Histories of Astronomy which inform one that the precession of the equinoxes was discovered by Hipparchus of Alexandria; but, surprisingly, there exists to my knowledge no modern History of Cosmology, no comprehensive survey of man's changing vision of the universe which encloses him.
The above explains what this book is aiming at, and what it is trying to avoid. It is not a history of astronomy, though astronomy comes in where it is needed to bring the vision into sharper focus; and, though aimed at the general reader, it is not a book of "popular science" but a personal and speculative account of a controversial subject. It opens with the Babylonians and ends with Newton, because we still live in an essentially Newtonian universe; the cosmology of Einstein is as yet in a fluid state, and it is too early to assess its influence on culture. To keep the vast subject within manageable limits, I could attempt only an outline. It is sketchy in parts, detailed in others, because selection and emphasis of the material was guided by my interest in certain specific questions, which are the leitmotifs of the book, and which I must briefly set out here.
Firstly, there are the twin threads of Science and Religion, starting with the undistinguishable unity of the mystic and the savant in the Pythagorean Brotherhood, falling apart and reuniting again, now tied up in knots, now running on parallel courses, and ending in the polite and deadly "divided house of faith and reason" of our day, where, on both sides, symbols have hardened into dogmas, and the common source of inspiration is lost from view. A study of the evolution of cosmic awareness in the past may help to find out whether a new departure is at least conceivable, and on what lines.
Secondly, I have been interested, for a long time, in the psychological process of discovery 2 as the most concise manifestation of man's creative faculty – and in that converse process that blinds him towards truths which, once perceived by a seer, become so heartbreakingly obvious. Now this blackout shutter operates not only in the minds of the "ignorant and superstitious masses" as Galileo called them, but is even more strikingly evident in Galileo's own, and in other geniuses like Aristotle, Ptolemy or Kepler. It looks as if, while part of their spirit was asking for more light, another part had been crying out for more darkness. The History of Science is a relative newcomer on the scene, and the biographers of its Cromwells and Napoleons are as yet little concerned with psychology; their heroes are mostly represented as reasoning-machines on austere marble pedestals, in a manner long outdated in the mellower branches of historiography – probably on the assumption that in the case of a Philosopher of Nature, unlike that of a statesman or conqueror, character and personality are irrelevant. Yet all cosmological systems, from the Pythagoreans to Copernicus, Descartes and Eddington, reflect the unconscious prejudices, the philosophical or even political bias of their authors; and from physics to physiology, no branch of Science, ancient or modern, can boast freedom from metaphysical bias of one kind or another. The progress of Science is generally regarded as a kind of clean, rational advance along a straight ascending line; in fact it has followed a zig-zag course, at times almost more bewildering than the evolution of political thought. The history of cosmic theories, in particular, may without exaggeration be called a history of collective obsessions and controlled schizophrenias; and the manner in which some of the most important individual discoveries were arrived at reminds one more of a sleepwalker's performance than an electronic brain's.
Thus, in taking down Copernicus or Galileo from the pedestal on which science-mythography has placed them, my motive was not to "debunk", but to inquire into the obscure workings of the creative mind. Yet I shall not be sorry if, as an accidental by-product, the inquiry helps to counteract the legend that Science is a purely rational pursuit, that the Scientist is a more "level-headed" and "dispassionate" type than others (and should therefore be given a leading part in world affairs); or that he is able to provide for himself and his contemporaries, a rational substitute for ethical insights derived from other sources.
It was my ambition to make a difficult subject accessible to the general reader, but students familiar with it will, I hope, nevertheless find some new information in these pages. This refers mainly to Johannes Kepler, whose works, diaries and correspondence have so far not been accessible to the English reader; nor does a serious English biography exist. Yet Kepler is one of the few geniuses who enables one to follow, step by step, the tortuous path that led him to his discoveries, and to get a really intimate glimpse, as in a slow-motion film, of the creative act. He accordingly occupies a key-position in the narrative.
Copernicus' magnum opus, On the Revolutions of the Heavenly Spheres, also had to wait until 1952 for a first English translation – which perhaps explains certain curious misunderstandings about his work, shared by practically all authorities who have written on the subject, and which I have tried to rectify.
The general reader is advised not to bother about the Notes at the end of the book; on the other hand, the reader with a scientific education is asked to forbear with explanations which might seem an insult to his intelligence. So long as in our educational system a state of cold war is maintained between the Sciences and the Humanities, this predicament cannot be avoided.
One significant step towards ending this cold war was Professor Herbert Butterfield Origins of Modern Science, first published in 1949. Apart from the work's profundity and excellence per se, I was much impressed by the fact that the Professor of Modern History in the University of Cambridge should venture into mediaeval Science and undertake such a gulf-bridging task. Perhaps this age of specialists is in need of creative trespassers. It was this shared conviction which made me ask Professor Butterfield for the favour of a short Introduction to another trespassing venture.
* * * * *
My sincere thanks are due to Professor Max Caspar, Munich, and to Bibliotheksrat Dr. Franz Hammer, Stuttgart, for help and advice on Johannes Kepler; to Dr. Marjorie Grene for her help on mediaeval Latin sources and various other problems; to Professor Zdenek Kopal, University of Manchester, for his critical reading of the text; to Professor Alexandre Koyré, École des Hautes Études, Sorbonne, and Professor Ernst Zinner, Bamberg, for information quoted in the Notes; to Professor Michael Polanyi for his sympathetic interest and encouragement; lastly to Miss Cynthia Jefferies for her unending patient labours on the typescript and galleys.
PART ONE THE HEROIC AGE
I DAWN
1. Awakening
WE can add to our knowledge, but we cannot subtract from it. When I try to see the Universe as a Babylonian saw it around 3000 B.C., I must grope my way back to my own childhood. At the age of about four I had what I felt to be a satisfactory understanding of God and the world. I remember an occasion when my father pointed hi
s finger at the white ceiling, which was decorated with a frieze of dancing figures, and explained that God was up there, watching me. I immediately became convinced that the dancers were God and henceforth addressed my prayers to them, asking for their protection against the terrors of day and night. Much in the same manner, I like to imagine, did the luminous figures on the dark ceiling of the world appear as living divinities to Babylonians and Egyptians. The Twins, the Bear, the Serpent were as familiar to them as my fluted dancers to me; they were thought to be not very far away, and they held power of life and death, harvest and rain.