Everything has changed, except our way of thinking.

Smoke like a chimney, work like a horse, eat without thinking, go for a walk only in really pleasant company.

Yes, we now have to divide up our time like that, between politics and our equations. But to me our equations are far more important, for politics are only a matter of present concern. A mathematical equation stands forever.

Many a young lady does not realize just how strong her love for a young man is until he fails to pass the approval test with her parents. There is no fear in love; but perfect love casteth out fear. Of all forms of caution, caution in love is the most fatal. There are only two truly infinite things, the universe and stupidity. And I am unsure about the universe.

God is a scientist, not a magician.

Only the Catholic Church protested against the Hitlerian onslaught on liberty. Up till then I had not been interested in the Church, but today I feel a great admiration for the Church, which alone has had the courage to struggle for spiritual truth and moral liberty

For the moral attitudes of a people that is supported by religion need always aim at preserving and promoting the sanity and vitality of the community and its individuals, since otherwise this community is bound to perish. A people that were to honour falsehood, defamation, fraud, and murder would be unable, indeed, to subsist for very long.