When a love-relationship is at its height there is no room left for any interest in the environment; a pair of lovers are sufficient to themselves

We know less about the sexual life of little girls than of boys. But we need not feel ashamed of this distinction; after all, the sexual life of adult women is a 'dark continent' for psychology.

The wish to be able to fly is to be understood as nothing else than a longing to be capable of sexual performance.

Whatever fosters the growth of civilization works at the same time against war.

Civilized people have exchanged some part of their chances of happiness for a measure of security.

A man like me cannot live without a hobby-horse, a consuming passion - in Schiller's words a tyrant. I have found my tyrant, and in his service I know no limits. My tyrant is psychology. It has always been my distant, beckoning goal and now since I have hit upon the neuroses, it has come so much the nearer.

Nature delights in making use of the same forms in the most various biological connections: as it does, for instance, in the appearance of branch-like structures both in coral and in plants, and indeed in some forms of crystal and in certain chemical precipitates.