Religion [is] the universal obsessional neurosis of humanity

A love that does not discriminate seems to me to forfeit a part of its own value, by doing an injustice to its object; and secondly, not all men are worthy of love.

Being entirely honest with oneself is a good exercise.

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.

In the depths of my heart I can’t help being convinced that my dear fellow-men, with a few exceptions, are worthless.

I consider it a good rule for letter-writing to leave unmentioned what the recipient already knows, and instead tell him something new.

Concerning the factors of silence, solitude and darkness, we can only say that they are actually elements in the production of the infantile anxiety from which the majority of human beings have never become quite free.