What is vanity but the longing to survive?

We should try to be the parents of our future rather than the offspring of our past.

Life is doubt, and faith without doubt is nothing but death.

Yes, yes, I see it all! — an enormous social activity, a mighty civilization, a profuseness of science, of art, of industry, of morality, and afterwords, when we have filled the world with industrial marvels, with great factories, with roads, museums and libraries, we shall fall exhausted at the foot of it all, and it will subsist — for whom? Was man made for science or was science made for man?

It is sad not to love, but it is much sadder not to be able to love.

And killing time is perhaps the essence of comedy, just as the essence of tragedy is killing eternity.

Man is said to be a reasoning animal. I do not know why he has not been defined as an affective or feeling animal. Perhaps that which differentiates him from other animals is feeling rather than reason. More often I have seen a cat reason than laugh or weep. Perhaps it weeps or laughs inwardly - but then perhaps, also inwardly, the crab resolves equations of the second degree.