There are vices which have no hold upon us, but in connection with others; and which, when you cut down the trunk, fall like the branches.

When I consider the small span of my life absorbed in the eternity of all time, or the small part of space which I can touch or see engulfed by the infinite immensity of spaces that I know not and that know me not, I am frightened and astonished to see myself here instead of there … now instead of then.

What part of us feels pleasure? Is it our hand, our arm, our flesh, or our blood? It must obviously be something immaterial.

Force rules the world-not opinion; but it is opinion that makes use of force.

Those who are accustomed to judge by feeling do not understand the process of reasoning, because they want to comprehend at a glance and are not used to seeking for first principles. Those, on the other hand, who are accustomed to reason from first principles do not understand matters of feeling at all, because they look for first principles and are unable to comprehend at a glance.

We sail within a vast sphere, ever drifting in uncertainty, driven from end to end.

Man is so made that by continually telling him he is a fool he believes it, and by continually telling it to himself he makes himself believe it. For man holds an inward talk with himself, which it pays him to regulate.