# Jacob Bronowski

Polish-born British mathematician

Jacob Bronowski (January 18, 1908August 22, 1974) was a British mathematician, biologist, and science historian of Polish origin. He is remembered in popular culture as the writer and presenter of the influential 1973 BBC television documentary series, The Ascent of Man.

Jacob Bronowski
The symbol and the metaphor are as necessary to science as to poetry.

## Quotes

The most remarkable discovery ever made by scientists, was science itself.

Science is nothing else then the search to discover unity in the wild variety of nature — or more exactly, in the variety of our experience.
• These are the moments when the powerful mind or the forceful character feels the ferment of the times, when his thoughts quicken, and when he can inject into the uncertainties of others the creative ideas which will strengthen them with purpose. At such a moment the man who can direct others, in thought or in action, can remake the world.
• The Common Sense of Science (1951), on the influence of Isaac Newton.
• The air in a man's lungs contains 10,000,000,000,000,000,000,000 atoms, so that sooner or later every one of us breathes an atom that has been breathed before by anyone you can think of who has ever lived — Michelangelo or George Washington or Moses.
• The Reader's Digest (1964) Vol. 84; also quoted in Structure and Plan (1974) by Glen A. Love, p. 154
• I grew up to be indifferent to the distinction between literature and science, which in my teens were simply two languages for experience that I learned together.
• As quoted in World Authors 1950–1970 (1975) by J. Wakeman, pp. 221–223
• The progress of science is the discovery at each step of a new order which gives unity to what had long seemed unlike. Faraday did this when he closed the link between electricity and magnetism. Clerk Maxwell did it when he linked both with light. Einstein linked time with space, mass with energy, and the path of light past the sun with the flight of a bullet; and spent his dying years in trying to add to these likenesses another, which would find a single imaginative order between the equations between Clerk Maxwell and his own geometry of gravitation When Coleridge tried to define beauty, he returned always to one deep thought: beauty he said, is "unity in variety." Science is nothing else than the search to discover unity in the wild variety of nature — or more exactly, in the variety of our experience.
• As quoted in The God Particle (1993) by Leon Lederman – ISBN 978–0–618–71168–0

### The Common Sense of Science (1951)

• I write... for laymen and scientists, because the reader who is interested in any activity which needs thought and judgement is... a person to whom science can be made to speak, It is not he who is deaf, but the specialists who have been dumb—the specialists in the arts as well as in the sciences.
• "Sense and Sensibility"
• [I]nterest, say in mathematics, has usually been killed by routine teaching, exactly as the literary interest... has been killed...
• "Sense and Sensibility"
• Science is not a special sense. It is as wide as the literal meaning of its name: knowledge. The notion of the specialized mind is... as modern as the specialized man, 'the scientist', a word which is only a hundred years old.
• "Sense and Sensibility"
• The belief that science destroys culture is sometimes supported by historical statements that the arts have flourished only when the sciences have been neglected. This thesis is... directly contrary to history... [I]n the great age of Greece, art and science penetrate one another more closely than in any modern age. ...The example of these men in science as much as in art set the modern world afire in the Renaissance. And the type and symbol of Renaissance man... remains Leonardo da Vinci, painter, sculptor, mathematician, and engineer. No man has shown more strikingly the universality and the unity of the intellect.
• "Sense and Sensibility"
• Ralegh's own circle, which turned Christopher Marlowe into a rationalist, was dominated by... Thomas Hariot. For navigation is dependent on astronomy; it went hand in hand with the new speculations about the world and the solar system... in turn, the voyages of the great navigators inspired the literature of Elizabethan England. The worlds of art and science and the physical world unfolded then together. It was not by accident that the first table of logarithms was published within a few years of the First Folio.
• "Sense and Sensibility"
• Blake and Coleridge and Wilberforce were... contemporaries of Arkwright and James Watt. Against this, those who hold the illusion that pre-industrial England was more sensitive and cultured, point to the misery of the manufacturing age. ...[T]errible evils ...are ...far older than 1800 and the machines. But in the factory these evils became naked and public; and the driving force for reform came from the men of the mill, from Robert Owen and the elder Peel.
• In their broad Augustan day, Scottish miners were legally still serfs, just as miners in Greece had always been slaves; and neither civilization thought anything amiss. ...It was the engine, it was the horsepower which created consideration for the horse; and the Industrial Revolution which created our sensibility.
• "Sense and Sensibility"
• [T]he invention of photography has made the painter and the patron lose interest in the likeness and transfer it to some more formal pattern. Our whole sensibility has been re-created by such subtle shifts.
• "Sense and Sensibility"
• Science and the arts shared the same language at the Restoration. They no longer seem to do so today. ...they lack the same language. And it is the business of each of us to make that one universal language which alone can unite art and science, and layman and scientist, in a common understanding.
• "Sense and Sensibility"
• Newton was born during Cromell's revolution in the troubled 1640s; he was eighteen at the Restoration in 1660; and he published the Principia during the intrigues which ended by bringing William of Orange to England in the revolution of 1688. These are the moments when the powerful or the forceful character feels the ferment of the times, when his thoughts quicken...
• "The Scientific Revolution and the Machine"
• Science is not an impersonal construction. It is no less, and no more, personal than any other form of communicated thought. ...Science searches the common experience of people; and it is made by people, and it has their style. ...The style of Newton's work, as much as the content, dominated science for two centuries... The science of an age, like its art or its music, has style... But it has content and structure too, larger than the work of any one man...
• "The Scientific Revolution and the Machine"

### Science and Human Values (1956, 1965)

First published as a series of three essays in Universities Quarterly (1956) based on lectures presented at MIT in 1953. The 1965 revised edition added a Socratic dialogue, "The Abacus and the Rose". (Page numbers in parentheses refer to the 1972 Harper & Row "Perennial Library" edition.)
• The discoveries of science, the works of art are explorations — more, are explosions, of a hidden likeness. The discoverer or the artist presents in them two aspects of nature and fuses them into one. This is the act of creation, in which an original thought is born, and it is the same act in original science and original art.
• Part 1: "The Creative Mind", §9 (p. 19)
• Science, like art, is not a copy of nature but a re-creation of her.
• Part 1: "The Creative Mind", §9 (p. 20)
• We re-make nature by the act of discovery, in the poem or in the theorem. And the great poem and the deep theorem are new to every reader, and yet are his own experience, because he himself re-creates them.
• Part 1: "The Creative Mind", §9 (p. 20)
• Mass, time, magnetic moment, the unconscious: we have grown up with these symbolic concepts, so that we are startled to be told that man had once to create them for himself. He had indeed, and he has: for mass is not an intuition in the muscle, and time is not bought ready-made at the watchmaker's.
• Part 2: "The Habit of Truth", §5 (p. 35)
• In effect what Luther said in 1517 was that we may appeal to a demonstrable work of God, the Bible, to override any established authority. The Scientific Revolution begins when Nicolaus Copernicus implied the bolder proposition that there is another work of God to which we may appeal even beyond this: the great work of nature. No absolute statement is allowed to be out of reach of the test, that its consequence must conform to the facts of nature.
The habit of testing and correcting the concept by its consequences in experience has been the spring within the movement of our civilization ever since. In science and in art and in self-knowledge we explore and move constantly by turning to the world of sense to ask, Is this so? This is the habit of truth, always minute yet always urgent, which for four hundred years has entered every action of ours; and has made our society and the value it sets on man.
• Part 2: "The Habit of Truth", §11 (p. 45–46)
• No fact in the world is instant, infinitesimal and ultimate, a single mark. There are, I hold, no atomic facts. In the language of science, every fact is a field — a crisscross of implications, those that lead to it and those that lead from it. … We condense the laws around concepts. Science takes its coherence, its intellectual and imaginative strength together, from the concepts at which its laws cross, like knots in a mesh.
• Part 3: "The Sense of Human Dignity", §1 (p. 52)
• Positivists and analysts alike believe that the words is and ought belong to different worlds, so that sentences which are constructed with is usually have verifiable meaning, but sentences constructed with ought never have. This is because Ludwig Wittgenstein's unit, and Bertrand Russell's unit, is one man; all British empiricist philosophy is individualist. And it is of course clear that if the only criterion of true and false which a man accepts is that man's, then he has no base for social agreement. The question of how man ought to behave is a social question, which always involves several people; and if he accepts no evidence and no judgment except his own, he has no tools with which to frame an answer.
• Part 3: "The Sense of Human Dignity", §3 (p. 56)
• There is a social injunction implied in the positivist and analyst methods. This social axiom is that
We OUGHT to act in such a way that what IS true can be verified to be so.
• Part 3: "The Sense of Human Dignity", §3 (p. 58)
• Has there ever been a society which has died of dissent? Several have died of conformity in our lifetime.
• Part 3: "The Sense of Human Dignity", §5 (p. 61)
• Tolerance among scientists cannot be based on indifference, it must be based on respect. Respect as a personal value implies, in any society, the public acknowledgements of justice and of due honor. These are values which to the layman seem most remote from any abstract study. Justice, honor, the respect of man for man: What, he asks, have these human values to do with science? [...]
Those who think that science is ethically neutral confuse the findings of science, which are, with the activity of science, which is not.
• Part 3: "The Sense of Human Dignity", §6 (p. 63–64)
• Nature is more subtle, more deeply intertwined and more strangely integrated than any of our pictures of her — than any of our errors. It is not merely that our pictures are not full enough; each of our pictures in the end turns out to be so basically mistaken that the marvel is that it worked at all.
• Part 4: "The Abacus and the Rose" (p. 98)
• The painter's portrait and the physicist's explanation are both rooted in reality, but they have been changed by the painter or the physicist into something more subtly imagined than the photographic appearance of things.
• Part 4: "The Abacus and the Rose" (p. 103)
• Dissent is the mark of freedom.
• (unsorted)
• There is today almost no scientific theory which was held when, say, the Industrial Revolution began about 1760. Most often today's theories flatly contradict those of 1760; many contradict those of 1900. In cosmology, in quantum mechanics, in genetics, in the social sciences, who now holds the beliefs that seemed firm sixty years ago? Yet the society of scientists has survived these changes without a revolution, and honors the men whose beliefs it no longer shares. No one has recanted abjectly at a trial before his colleagues. The whole structure of science has been changed and no one has been either disgraced or deposed. Through all the changes of science, the society of scientists is flexible and single-minded together, and evolves and rights itself. In the language of science, it is a stable society.

### The Creative Process, 1958

J. Bronowski. "The Creative Process." Scientific American 199:59; September 1958.

• The most remarkable discovery made by scientists is science itself. The discovery must be compared in importance with the invention of cave-painting and of writing. Like these earlier human creations, science is an attempt to control our surroundings by entering into them and understanding them from inside. And like them, science has surely made a critical step in human development which cannot be reversed. We cannot conceive a future society without science. I have used three words to describe these far - reaching changes : discovery, invention and creation. There are contexts in which one of these words is more appropriate than the others.
• Christopher Columbus discovered the West Indies, and Alexander Graham Bell invented the telephone. We do not call their achievements creations because they are not personal enough. The West Indies were there all the time; and as for the telephone, we feel that Bell's ingenious thought was somehow not fundamental. The groundwork was there, and if not Bell then someone else would have stumbled on the telephone almost as accidently as on the West Indies.
By contrast, we feel that Othello is genuinely a creation. This is not because Othello came out of a clear sky; it did not. There were Elizabethan dramatists before William Shakespeare, and without them he could not have written as he did. Yet within their tradition Othello remains profoundly personal; and though every element in the play has been a theme of other poets, we know that the amalgam of these elements is Shakespeare's; we feel the presence of his single mind. The Elizabethan drama would have gone on without Shakespeare, but no one else would have written Othello...
• p. 97-98: As quoted in: S.P. Sector (‎1997). A Study of Issues Relating to the Patentability of Biotechnological Subject Matter. Footnote 51.
• A fact is discovered, a theory is invented; is any theory ever deep enough for it to be truly called a creation? Most scientists would answer: no! Science, they would say, engages only part of the mind - the rational intellect - but creation must engage the whole mind. Science demands none of that ground swell of emotion, none of the rich bottom of personality, which fills out the work of art...
Creation consists in finding unity, finding likenesses, finding pattern...
Nature herself is chaos; she is full of infinite variety without order. But if you see her with inner vision, a creative mind (whether a poetic mind like Charles Baudelaire's or a scientific mind like Isaac Newton's), there comes a moment when many different aspects suddenly crystallize in a single unity. You have found a key; you have found a clue; you have found the path which organizes the material. You have found what Coleridge called "unity in variety." That is the moment of creation.
• p. 97-98: As quoted in: S.P. Sector (‎1997). A Study of Issues Relating to the Patentability of Biotechnological Subject Matter. Footnote 51.

### "The Reach of Imagination" (1967)

• To imagine is the characteristic act, not of the poet's mind, or the painter's, or the scientist's, but of the mind of man.
• To imagine means to make images and to move them about inside one's head in new arrangements.
• With the... symbolic memory we spell out the future—not one but many futures, which we weigh one against another.
• I am using the word image in a wide meaning, which does not restrict it to the mind's eye as a visual organ. An image in my usage is what Charles Pierce called a sign...
• [T]he most important images for human beings are simply words, which are abstract symbols. ...[E]volution has greatly enlarged the front lobes of the human brain, which govern the sense of the past and the future; and... they are probably the seat of our other images.
• The images play out for us events which are not present in our senses, and... create the future—a future that... may never come to exist in that form.
• Almost everything that we do that is worth doing is done in the first place in the mind's eye.
• The richness of human life is that we have many lives, we live the events that do not happen (and some that cannot) as vividly as those that do, and if thereby we die a thousand deaths, that is the price we pay...
• Imagination is the manipulation of images in one's head... the rational manipulation... as well as the literary and artistic manipulation.
• When a child begins to play games... he enters the gateway to reason and imagination together.
• [T]he human reason discovers new relations between things not by deduction, but by that unpredictable blend of speculation and insight... induction, which—like other forms of imagination—cannot be formalized.
• The strength of the imagination, its enriching power and excitement, lies in its interplay with reality—physical and emotional.
• All great scientists have used their imaginations freely, and let it ride them to outrageous conclusions without crying "Halt!"
• The symbol is the tool which gives man his power, and it is the same tool whether the symbols are images or words, mathematical signs or mesons.
• [S]ymbols have a reach and a roundness that goes beyond their literal and practical meaning. They are the rich concepts under which the mind gathers many particulars into one name, and many instances into one general induction.
• When a man counts one, two, three, he is not only doing mathematics, he is on the path to the mysticism of numbers in Pythagoras and Vitruvius and Kepler, to the Trinity and the signs of the Zodiac.
• [I]magination... is the faculty... the common root from which science and literature... spring and grow and flourish together. ...the great ages of science are the great ages of all the arts... [P]owerful minds have taken fire from one another... without asking... to tie their imagination to falling balls or a haunted island. ...When Galileo was looking through his telescope at the moon, Shakespeare was writing The Tempest and all Europe was in ferment, from Johannes Kepler to Peter Paul Rubens, and from the first table of logarithms by John Napier to the Authorized version of the Bible.
• Let me end with... man's ageless fantasy, to fly to the moon. ...Plutarch and Lucian, Ariosto and Ben Jonson wrote about it, before the days of Jules Verne and H. G. Wells and science fiction. The seventeenth century was heady with... fables about voyages to the moon. Kepler wrote one full of deep scientific ideas... Francis Godwin wrote... The Man in the Moone... John Wilkins wrote... The Discovery of a New World. They did not draw a line between science and fancy... they all tried to guess where... earth's gravity would stop. Only Kepler understood that gravity has no boundary, and put a law to it—... the wrong law.
All this was a few years before Isaac Newton was born, and it was all in his head that day in 1666, when he... came to conceive... that the moon is like a ball... thrown so hard that it falls exactly as fast as the horizon... he went on to calculate how long... the distant moon would take to round the earth... [T]he imagination that day chimed with nature, and made a harmony.

### The Ascent of Man (1973)

• In every age there is a turning point, a new way of seeing and asserting the coherence of the world. It is frozen in the statues of Easter Island that put a stop to time—and in the medieval clocks of Europe that once also seemed to say the last word about the heavens for ever. Each culture tries to fix its visionary moment, when it was transformed by a new conception either of nature or of man. But in retrospect, what commands our attention as much are the continuities—the thoughts that run or recur from one civilization to another.
• Ch. 1 Lower than the Angels.
• Man is not the most majestic of the creatures; long before the mammals even, the dinosaurs were far more splendid. But he has what no other animal possesses: a jigsaw of faculties, which alone, over three thousand million years of life, made him creative. Every animal leaves traces of what he was. Man alone leaves traces of what he created.
• In a parched African landscape like this at Omo, man first put his foot to the ground. That seems a pedestrian way to begin the ascent of man.
• Episode 1: "Lower than the Angels"
• Of course it's tempting to close one's eyes to history, and instead speculate about the roots of war in some possible animal instinct: as if, like the tiger, we still had to kill to live, or, like the robin redbreast, to defend a nesting territory. But war, organized war, is not a human instinct. It is a highly planned and cooperative form of theft. And that form of theft began 10,000 years ago when the harvesters of wheat accumulated a surplus and the nomads rose out of the desert to rob them of what they themselves could not provide. The evidence for that, we saw, in the walled city of Jericho and its prehistoric tower... That is the beginning of war.
• Episode 2: "The Harvest of the Seasons"
• One aim of the physical sciences has been to give an exact picture of the material world. One achievement of physics in the twentieth century has been to prove that that aim is unattainable. There is no absolute knowledge and those who claim it, whether they are scientist or dogmatist, open the door to tragedy. All knowledge, all information is imperfect. We have to treat it with humility.
• Episode 11: "Knowledge or Certainty"
• The symbol of the University is the iron statue outside the Rathskeller of a barefoot goose girl that every student kisses at graduation. The University is a Mecca to which students come with something less than perfect faith. It is important that students bring a certain ragamuffin, barefoot irreverence to their studies; they are not here to worship what is known but to question it.
• Episode 11: "Knowledge or Certainty"
• The Principle of Uncertainty is a bad name. In science, or outside of it, we are not uncertain; our knowledge is merely confined, within a certain tolerance. We should call it the Principle of Tolerance. And I propose that name in two senses. First, in the engineering sense: Science has progressed, step by step, the most successful enterprise in the ascent of man, because it has understood that the exchange of information between man and nature, and man and man, can only take place with a certain tolerance. But second, I also use the word, passionately, about the real world. All knowledge – all information between human beings – can only be exchanged within a play of tolerance. And that is true whether the exchange is in science, or in literature, or in religion, or in politics, or in any form of thought that aspires to dogma. It's a major tragedy of my lifetime and yours that scientists were refining, to the most exquisite precision, the Principle of Tolerance – and turning their backs on the fact that all around them, tolerance was crashing to the ground beyond repair. The Principle of Uncertainty or, in my phrase, the Principle of Tolerance, fixed once for all the realization that all knowledge is limited. It is an irony of history that at the very time when this was being worked out, there should rise, under Hitler in Germany and other tyrants elsewhere, a counter-conception: a principle of monstrous certainty. When the future looks back on the 1930's, it will think of them as a crucial confrontation of culture as I have been expounding it – the ascent of man against the throwback to the despots' belief that they have absolute certainty.
• Episode 11: "Knowledge or Certainty"
• It's said that science will dehumanize people and turn them into numbers. That's false, tragically false. Look for yourself. This is the concentration camp and crematorium at Auschwitz. This is where people were turned into numbers. Into this pond were flushed the ashes of some four million people. And that was not done by gas. It was done by arrogance, it was done by dogma, it was done by ignorance. When people believe that they have absolute knowledge, with no test in reality, this is how they behave. This is what men do when they aspire to the knowledge of gods.

Science is a very human form of knowledge. We are always at the brink of the known; we always feel forward for what is to be hoped. Every judgment in science stands on the edge of error and is personal. Science is a tribute to what we can know although we are fallible. In the end, the words were said by Oliver Cromwell: "I beseech you in the bowels of Christ: Think it possible you may be mistaken."

I owe it as a scientist to my friend Leo Szilard, I owe it as a human being to the many members of my family who died here, to stand here as a survivor and a witness. We have to cure ourselves of the itch for absolute knowledge and power. We have to close the distance between the push-button order and the human act. We have to touch people.

• Episode 11: "Knowledge or Certainty"
• Fifty years from now, if an understanding of man's origins, his evolution, his history, his progress is not in the common place of the school books, we shall not exist.
• Episode 13: "The Long Childhood"
• And I am infinitely saddened to find myself suddenly surrounded in the west by a sense of terrible loss of nerve, a retreat from knowledge into—into what? Into Zen Buddhism; into falsely profound questions about, Are we not really just animals at bottom; into extra-sensory perception and mystery. They do not lie along the line of what we are able to know if we devote ourselves to it: an understanding of man himself. We are nature’s unique experiment to make the rational intelligence prove itself sounder than the reflex. Knowledge is our destiny. Self-knowledge, at last bringing together the experience of the arts and the explanations of science, waits ahead of us.
• Episode 13: "The Long Childhood"
• The world can only be grasped by action, not by contemplation.
• Unidentified episode
• We are all afraid - for our confidence, for the future, for the world. That is the nature of the human imagination. Yet every man, every civilization, has gone forward because of its engagement with what it has set itself to do. The personal commitment of a man to his skill, the intellectual commitment and the emotional commitment working together as one, has made the Ascent of Man.
• Sourced to the book, The Ascent of Man (1973), BBC Books: London, Chapter 13: The Long Childhood, p. 330.

### The Origins of Knowledge and Imagination (1978)

• Since the word "knowledge" occurs in my general title... I am going to be talking about epistemology, although I prefer to use the eighteenth-century, indeed, medieval phrase, "natural philosophy." ...that enterprise of the human mind which attempts to trace lawfulness to nature, dead and living, but which is not directed to specific inquiries into how this or that law works. Philosophy in the sense in which I practice it, natural philosophy, is concerned with lawfulness rather than with laws and the general nature of laws rather than with the specific structure of this or that law. Natural philosophy was one of the three topics (moral philosophy and metaphysical philosophy were the others) to which one graduated in medieval universities after having studied the seven liberal arts.
I believe that we need to review the whole of our natural philosophy in the light of scientific knowledge that has arisen in the last fifty years.
• What we really mean by free will... is the visualizing of alternatives and making a choice between them. ...the central problem of human consciousness depends on this ability to imagine.
• I believe that the world is totally connected: that is to say, that there are no events anywhere in the universe which are not tied to every other event in the universe. ...It is... an essential part of the methodology of science to divide the world for any experiment into... relevant and... irrelevant. We make a cut. We put the experiment... into a box. ...the moment we do that, we do violence to the connections ...I get a set of answers which I try to decode in this context. ...I am certainly not going to get the world right, because the basic assumption that I have made about the world is a lie. ...it is bound to give me only an approximation to what goes inside the fence. Therefore, when we practice science (and this is true of all our experience) we are always decoding a part of nature which is not complete. We simply cannot get out of our own finiteness.
• Let me close by reminding you of what Newton actually did on the day that he conceived ${\displaystyle G=k{\frac {mm'}{r^{2}}}}$ . ...Newton did not have any subsidies, grants, funds, Secret Service money. But he had the moon. He said, "... I cannot throw a ball round the world, but let me picture the moon as if it were a ball which has been flung around the world... How long will it take to go round the world?" ...He knew the value of gravity at the earth's surface ...but he did not know the value of the earth's gravity for the moon. He said, "Let us suppose that it is given by an inverse square law. Now, how long will it take the moon to go around?" It comes out at twenty-eight days. As Newton said, "They agreed pretty nearly."
• Progress is the exploration of our own error. Evolution is a consolidation of what have always begun as errors. And errors are of two kinds: errors that turn out to be true and errors that turn out to be false (which are most of them). But they both have the same character of being an imaginative speculation. ...it seems to me terribly important to say this in an age in which most nonscientists are feeling a kind of loss of nerve. ...by the time science becomes a closed—that is, computerizable—project, it is not science anymore. It is not in the area of the exploration of errors.

### "The Imaginative Mind in Art" (1978)

in The Visonary Eye, ed., Jacob Bronowski
• [A]ll our symbols have the same purpose; words are merely the symbols we use most commonly. The function of words in human thought is to stand for things which are not present to the senses, and allow the mind to manipulate them—things, concepts, ideas, everything that does not have a physical reality in front of us now.
• The language of ideas creates a different universe: a universe which has multiplied the monkey's vocabulary of forty words to the million words in the English dictionary.
• Human beings can imagine situations which are different from those in front of their eyes... because they make and hold in their minds images for absent things.
• When a child... discovers his own imagination, he suddenly walks into a new life. ...seeing situations that do not exist. ...in part as fantasy, and in part as a quite rational exploration of future experiences. ...play ...frolics in the fantasy world, and it experiments in the rational world... They project themselves into all worlds, possible and impossible, and discover for themselves the knife-edge boundary between them.
• The ability... to experiment with imaginary situations, gives man a freedom... the pleasure in trying out and exploring imaginary situations. A child's play is concerned with this pleasure; and so is much of art, and much of science... [P]ure science... is a form of play, in this sense.