The human race may well become extinct before the end of the century.

Mathematics rightly viewed possesses not only truth but supreme beauty.

I know a parson who frightened his congregation terribly by telling them the second coming was very imminent indeed, but they were much consoled when they found he was planting trees in his garden.

We have in fact, two kinds of morality, side by side: one which we preach, but do not practice, and another which we practice, but seldom preach.

Hatred of enemies is easier and more intense than love of friends. But from men who are more anxious to injure opponents than to benefit the world at large no great good is to be expected.

What hunger is in relation to food, zest is in relation to life.

Almost everything that distinguishes the modern world from earlier centuries is attributable to science, which achieved its most spectacular triumphs in the seventeenth century.