Overcoming difficulties leads to courage, self-respect, and knowing yourself.

Man knows much more than he understands.

To all those who walk the path of human cooperation war must appear loathsome and inhuman.

Exaggerated sensitiveness is an expression of the feeling of inferiority.

There is a courage of happiness as well as a courage of sorrow.

In the company of friends, writers can discuss their books, economists the state of the economy, lawyers their latest cases, and businessmen their latest acquisitions, but mathematicians cannot discuss their mathematics at all. And the more profound their work, the less understandable it is.

Far more unwaveringly, the neurotic keeps before his eye his God, his idol, his ideal of personality and clings to his guiding principle, losing sight in the meanwhile of reality, whereas the normal person is always ready to dispense with this crutch, this aid, and reckon unhampered with reality.