Dreams are the guardians of sleep and not its disturbers.

Might we not say that every child at play behaves like a creative writer, in that he creates a world of his own, or, rather, rearranges the things of his world in a new way which pleases him?

An intimate friend and a hated enemy have always been indispensable requirements for my emotional life; I have always been able to create them anew, and not infrequently my childish ideal has been so closely approached that friend and enemy coincided in the same person.

Writers write for fame, wealth, power and the love of women.

The communal life of human beings had . . . a two-fold foundation: the compulsion to work, which was created by external necessity, and the power of love.

The reproaches against science for not having yet solved the problems of the universe are exaggerated in an unjust and malicious manner; it has truly not had time enough yet for these great achievements. Science is very young--a human activity which developed late.

Men are not gentle, friendly creatures wishing for love, who simply defend themselves if they are attacked, but ... a powerful measure of desire for aggression had to be reckoned as part of their instinctual endowment.