In the moment of appreciation we live again the moment when the creator saw and held the hidden likeness.

We have to understand that the world can only be grasped by action, not by contemplation. The hand is more important than the eye ... The hand is the cutting edge of the mind.

There is no absolute knowledge. And those who claim it, whether they are scientists or dogmatists, open the door to tragedy.

[John] Dalton was a man of regular habits. For fifty-seven years he walked out of Manchester every day; he measured the rainfall, the temperature-a singularly monotonous enterprise in this climate. Of all that mass of data, nothing whatever came. But of the one searching, almost childlike question about the weights that enter the construction of these simple molecules-out of that came modern atomic theory. That is the essence of science: ask an impertinent question, and you are on the way to the pertinent answer.

By the worldly standards of public life, all scholars in their work are of course oddly virtuous. They do not make wild claims, they do not cheat, they do not try to persuade at any cost, they appeal neither to prejudice nor to authority . . .

Every judgment in science stands on the edge of error, and is personal.

It is not the business of science to inherit the earth, but to inherit the moral imagination; because without that, man and beliefs and science will perish together.