Nature is an infinite sphere of which the center is everywhere and the circumference nowhere.

Two things control men's nature, instinct and experience.

Man's true nature being lost, everything becomes his nature as, his true good being lost, everything becomes his good.

Our nature consists in motion complete rest is death.

Habit is a second nature that destroys the first. But what is nature? Why is habit not natural? I am very much afraid that nature itself is only a first habit, just as habit is a second nature.

The least movement is of importance to all nature. The entire ocean is affected by a pebble.

Man is but a reed, the most feeble thing in nature, but he is a thinking reed.

Custom is our nature. What are our natural principles but principles of custom?

Our soul is cast into a body, where it finds number, time, dimension. Thereupon it reasons, and calls this nature necessity, and can believe nothing else.

Can anything be stupider than that a man has the right to kill me because he lives on the other side of a river and his ruler has a quarrel with mine, though I have not quarrelled with him?