To be free means to be independent, not to be influenced by what others think and say.

I believe that whoever tries to think things through honestly will soon recognize how unworthy and even fatal is the traditional bias against Negroes. What can the man of good will do to combat this deeply rooted prejudice? He must have the courage to set an example by words and deed, and must watch lest his children become influenced by racial bias.

Scientific research is based on the idea that everything that takes place is determined by laws of Nature, and therefore this holds for the action of people. For this reason, a research scientist will hardly be inclined to believe that events could be influenced by a prayer, i.e. by a wish addressed to a Supernatural Being.

I never allow myself to become discouraged under any circumstances. The three great essentials to achieve anything worthwhile are first, hard work, second, stick-to-ittiveness, third, common sense.

The single most important decision any of us will ever make is whether or not to believe the universe is friendly.

If I am right the Germans will say I was a German, and the French will say I was a Jew; If I am wrong the Germans will say I was a Jew and the French will say I was a German.

An evening everyone agrees, is a lost evening.