Rejoice with your family in the beautiful land of life.

I know that it is a hopeless undertaking to debate about fundamental value judgements. For instance, if someone approves, as a goal, the extirpation of the human race from the earth, one cannot refute such a viewpoint on rational grounds. But if there is agreement on certain goals and values, one can argue rationally about the means by which these objectives may be obtained.

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

If we have the courage to decide ourselves for peace we will have peace.

The most valuable thing a teacher can impart to children is not knowledge and understanding per se but a longing for knowledge and understanding, and an appreciation for intellectual values, whether they be artistic, scientific, or moral. It is the supreme art of the teacher to awaken joy in creative expression and knowledge. Most teachers waste their time by asking questions that are intended to discover what a pupil does not know, whereas the true art of questioning is to discover what the pupil does know or is capable of knowing.

It is easier to denature plutonium than to denature the evil spirit of man.

Hunger, love, pain, fear are some of those inner forces which rule the individual's instinct for self preservation.