Opinions which justify cruelty are inspired by cruel impulses.

I've made an odd discovery. Every time I talk to a savant I feel quite sure that happiness is no longer a possibility. Yet when I talk with my gardener, I'm convinced of the opposite.

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

The human animal, like others, is adapted to a certain amount of struggle for life [and] the mere absence of effort from his life removes an essential ingredient of happiness. [. . .] He forgets that to be without some of the things you want is an indispensable part of happiness.

Man can be scientifically manipulated.

All religions are both harmful and untrue.

Ignore fact and reason, live entirely in the world of your own fantastic and myth-producing passions; do this whole-heartedly and with conviction, and you will become one of the prophets of your age.