I find myself regarding existence as though from beyond the tomb, from another world; all is strange to me; I am, as it were, outside my own body and individuality; I am depersonalized, detached, cut adrift. Is this madness?

Common sense is the measure of the possible; it is composed of experience and prevision; it is calculation applied to life.

Great men are true men, the men in whom nature has succeeded. They are not extraordinary - they are in the true order. It is the other species of men who are not what they ought to be.

The obscure only exists that it may cease to exist. In it lies the opportunity of all victory and all progress. Whether it call itself fatality, death, night, or matter, it is the pedestal of life, of light, of liberty and the spirit. For it represents resistance -- that is to say, the fulcrum of all activity, the occasion for its development and its triumph.

Men prefer the false due to habit, passion, will. Preference for truth is rare. Men are ruled by their fear of truth.

Thought is a kind of opium; it can intoxicate us, while still broad awake; it can make transparent the mountains and everything that exists.

Every living being seeks instinctively to complete itself.