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

Theories pass. The frog remains.

To be adult is to be alone.

What makes our opponents useful is that they allow us to believe that without them we would be able to realize our goals.

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.

Science has made us gods even before we are worthy of being men.

We spend our time envying people whom we wouldn't wish to be.