There are three creative ideas which, each in its turn, have been central to science. They are the idea of order, the idea of causes, and the idea of chance.

The most remarkable discovery ever made by scientists is science itself. The discovery must be compared in importance with the invention of cave-painting and of writing.

The basis for poetry and scientific discovery is the ability to comprehend the unlike in the like and the like in the unlike.

A man becomes creative, whether he is an artist or scientist, when he finds a new unity in the variety of nature. He does so by finding a likeness between things which were not thought alike before.

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.

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.

The hand is the cutting edge of the mind.