In two weeks the sheeplike masses of any country can be worked up by the newspapers into such a state of excited fury that men are prepared to put on uniforms and kill and be killed, for the sake of the sordid ends of a few interested parties. Compulsory military service seems to me the most disgraceful symptom of that deficiency in personal dignity from which civilized mankind is suffering today.

The only mistake in life is the lesson not learned.

There is nothing divine about morality; it is a purely human affair. If people are good only because they fear punishment, and hope for reward, then we are a sorry lot indeed. What the individual can do is to give a fine example, and to have the courage to uphold ethical values .. in a society of cynics.

If you're not sure why you're doing something, you can never do enough of it. Imagination is more important than knowledge.

James Clerk Maxwell's [work is the] most profound and the most fruitful.

The trite objects of human efforts-possessions, superficial success, luxury-have always seemed contemptible to me.

I refuse to make money out of my science. My laurel is not for sale like so many bales of cotton.