Man usually avoids attributing cleverness to somebody else unless it is an enemy.

Striving for peace and preparing for war are incompatible with each other, and in our time more so than ever.

Knowledge of what is does not open the door directly to what should be.

Discussion and argument are essential parts of science; the greatest talent is the ability to strip a theory until the simple basic idea emerges with clarity.

It was the experience of mystery - even if mixed with fear - that engendered religion.

I believe, indeed, that overemphasis on the purely intellectual attitude, often directed solely to the practical and factual, in our education, has led directly to the impairment of ethical values. I am not thinking so much of the dangers with which technical progress has directly confronted mankind, as of the stifling of mutual human considerations by a 'matter-of-fact' habit of thought which has come to lie like a killing frost upon human relations. Without 'ethical culture' there is no salvation for humanity.

Common sense is the collection of prejudices acquired by age eighteen.