It is sometimes important for science to know how to forget the things she is surest of.

The least one can say of power is that a vocation for it is suspicious.

Science had better not free the minds of men too much, before it has tamed their instincts.

Literature: proclaiming in front of everyone what one is careful to conceal from one's immediate circle

Somebody told me I should put a pebble in my mouth to cure my stuttering. Well, I tried it, and during a scene I swallowed the pebble. That was the end of that.

To say of men that they are bad is to say they are worse than we think we are, or worse than the ideal man whose image we have built up on the basis of a certain few.

If a given scientist had not made a given discovery, someone else would have done so a little later. Johann Mendel dies unknown after having discovered the laws of heredity: thirty-five years later, three men rediscover them. But the book that is not written will never be written. The premature death of a great scientist delays humanity; that of a great writer deprives it.