In early youth, as we contemplate our coming life, we are like children in a theatre before the curtain is raised, sitting there in high spirits and eagerly waiting for the play to begin.

In the sphere of thought, absurdity and perversity remain the masters of the world, and their dominion is suspended only for brief periods.

Every human perfection is linked to an error which it threatens to turn into

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.

Life is short and truth works far and lives long: let us speak the truth.

Women remain children all their lives, for they always see only what is near at hand, cling to the present, take the appearance of a thing for reality, and prefer trifling matters to the most important.

Consider the Koran... this wretched book was sufficient to start a world-religion, to satisfy the metaphysical need of countless millions for twelve hundred years, to become the basis of their morality and of a remarkable contempt for death, and also to inspire them to bloody wars and the most extensive conquests. In this book we find the saddest and poorest form of theism. Much may be lost in translation, but I have not been able to discover in it one single idea of value.