Rascals are always sociable, more's the pity! and the chief sign that a man has any nobility in his character is the little pleasure he takes in others' company.

Physics is unable to stand on its own feet, but needs a metaphysics on which to support itself, whatever fine airs it may assume towards the latter.

To desire immortality is to desire the eternal perpetuation of a great mistake

Truth is no harlot who throws her arms round the neck of him who does not desire her; on the contrary, she is so coy a beauty that even the man who sacrifices everything to her can still not be certain of her favors.

A poet or philosopher should have no fault to find with his age if it only permits him to do his work undisturbed in his own corner; nor with his fate if the corner granted him allows of his following his vocation without having to think about other people.

...this our world, which is so real, with all its suns and milky ways is-nothing.

If children were brought into the world by an act of pure reason alone, would the human race continue to exist? Would not a man rather have so much sympathy with the coming generation as to spare it the burden of existence, or at any rate not take it upon himself to impose that burden upon it in cold blood?