You cannot prepare for war and peace at the same time.

A model should be as simple as it can be but no simpler

We must recognize what in our accepted tradition is damaging to our fate and dignity-and shape our lives accordingly.

As long as there will be a man, there will be wars.

A conviction akin to religious feeling of the rationality or intelligibility of the world lies behind all scientific work of a high order.

You think you have troubles with mathematics . . . I assure you mine are still bigger.

If I were to remain silent, I'd be guilty of complicity.