There is only one reason for an individual to side-step to the useless side : the fear of a defeat on the useful side.

Tears and complaints - the means which I have called water power - can be an extremely useful weapon for disturbing cooperation and reducing other to a condition of slavery.

Each generation has its few great mathematicians, and mathematics would not even notice the absence of the others. They are useful as teachers, and their research harms no one, but it is of no importance at all. A mathematician is great or he is nothing.

The truth is often a terrible weapon of aggression. It is possible to lie, and even to murder, with the truth.

It is one of the most effective attitudes of the neurotic to measure thumbs down, so to speak, a real person by an ideal, since in doing so he can depreciate him as much as he wishes.

Every neurotic is partly in the right.

It is from among such individuals that all human failures spring.