Creativity is intelligence having fun.

The world needs heroes and it's better they be harmless men like me than villains like Hitler

We cannot despair of humanity, since we ourselves are human beings.

The years of searching in the dark for a truth that one feels but cannot express, the intense desire and the alternations of confidence and misgiving until one breaks through to clarity and understanding, are known only to him who has experienced them himself.

(Reply on what constitutes scientific proof:)"The question is much too difficult for me.

My intellectual development was retarded, as a result of which I began to wonder about space and time only when I had already grown up.

When men are engaged in war and conquest, the tools of science become as dangerous as a razor in the hands of a child of three. We must not condemn man because his inventiveness and patient conquest of the forces of nature are being exploited for false and destructive purposes. Rather, we should remember that the fate of mankind hinges entirely upon man’s moral development.