Envy ... is one form of a vice, partly moral, partly intellectual, which consists in seeing things never in themselves but only in their relations.

Be isolated, be ignored, be attacked, be in doubt, be frightened, but do not be silenced.

Americans and Englishmen, when they become acquainted with the Balkans, feel an astonished contempt when they study the mutual enmities of Bulgarians and Serbs, of Hungarians and Rumanians. It is evident to them that these enmities are absurd and that the belief of each little nation in its own superiority has no objective basis. But most of them are quite unable to see that the national pride of a Great Power is essentially as unjustifiable as that of a little Balkan country.

Science, in its ultimate ideal, consists of a set of propositions arranged in a hierarchy, the lowest level of the hierarchy being concerned with particular facts, and the highest with some general law, governing everything in the universe. The various levels in the hierarchy have a two-fold logical connection, travelling one up, one down; the upward connection proceeds by induction, the downward by deduction.

He will see himself and life and the world as truly as our human limitations will permit; realizing the brevity and minuteness of human life, he will realize also that in individual minds is concentrated whatever of value the known universe contains. And he will see that the man whose mind mirrors the world becomes in a sense as great as the world. In emancipation from the fears that beset the slave of circumstance he will experience a profound joy, and through all the vicissitudes of his outward life he will remain in the depths of his being a happy man.

Human life, its growth, its hopes, fears, loves, et cetera, are the result of accidents

Pure mathematics consists entirely of assertions to the effect that, if such and such a proposition is true of anything, then suchand such another proposition is true of that thing.... Thus mathematics may be defined as the subject in which we never know what we are talking about, nor whether what we are saying is true.