Jacob Bronowski Quotes

If any ideas have a claim to be called creative, because they have created something, then certainly it is the ideas of science.

[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 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.

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 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.

Science changes our values in two ways. It injects new ideas into the familiar culture. And it subjects it to the pressure of technical change, in the way I have just been describing, until the whole basis of our culture has imperceptibly been remade.

The world can only be grasped by action, not by contemplation. The hand is the cutting edge of man.

Let me close by reminding you of what Newton actually did on the day that he conceived <math>G = k \frac{mm'}{r^2}</math>. ...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."

The brain cannot reach its inner conclusions by any logic of certainty. In place of this, the brain must do two things. It must be content to accept less than certain knowledge. And it must have statistical methods which are different in kind from ours, by which it reaches its acceptable level of uncertainty. By these means, the brain constructs a picture of the world which is less than certain yet highly interlocked in its parts.

It has a special biological character. Let us take one simple, down-to-earth criterion for that: we are the only species in which the female has orgasms. That is remarkable, but it is so. It is a mark of the fact that in general there is much less difference between men and women (in the biological sense and in sexual behaviour) than there is in other species. That may seem a strange thing to say. But to the gorilla and the chimpanzee, where there are enormous differences between male and female, it would be obvious. In the language of biology, sexual dimorphism is small in the human species.

I have chosen to talk about one of the founder fathers of twentieth-century physics, Niels Bohr, because in both these respects he was a consummate artist. He had no ready-made answers. He used to begin his lecture courses by saying to his students, ‘Every sentence that I utter should be regarded by you not as an assertion but as a question’. What he questioned was the structure of the world. And the people that he worked with, when young and old (he was still penetrating in his seventies), were others who were taking the world to pieces, thinking it out, and putting it together.

If we act like other men, what shall we do on the day of the Lord, the day on which the pious will receive their reward, when a herald will proclaim: Where is He that weigheth the deeds of men, where is He that counteth?

In order to act in a scientific manner, in order to act in a human manner at all, two things are necessary: fact and thought. Science does not consist only a finding the facts; nor is it enough only to think, however rationally. The processes of science are characteristic of human action in that they move by the union of empirical fact and rational thought, in a way which cannot be disentangled.

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.

It has been one of the most destructive modern prejudices that art and science are different and somehow incompatible interests. We have fallen into the habit of opposing the artistic to the scientific tempers; we even identify them with a creative and a critical approach.