It is sometimes important for science to know how to forget the things she is surest of.
A man is not old as long as he is seeking something.
What makes our opponents useful is that they allow us to believe that without them we would be able to realize our goals.
The biologist passes. The frog stays the same.
Theories pass. The frog remains.
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.