Do not worry about your difficulties in Mathematics. I can assure you mine are still greater.

Man like every other animal is by nature indolent. If nothing spurs him on, then he will hardly think, and will behave from habit like an automaton.

I must seem like an ostrich who forever burries its head in the relativistic sands in order not to face the evil quanta.

I believe serious progress (in the abolition of war) can be achieved only when men become organized on an international scale and refuse, as a body, to enter military or war service.

In matters of truth and justice, there is no difference between large and small problems, for issues concerning the treatment of people are all the same.

God always takes the simplest way.

The enormous mental resilience, without which no Chess player can exist, was so much taken up by Chess that he could never free his mind of this game