The finest and healthiest thing about science is, as in the mountains, the brisk air blowing around in it.--The spiritually delicate (such as artists) shun and slander science owing to this air.

Everything is the same, nothing is worthwhile, the world is senseless, knowledge strangles.

There is more wisdom in your body than in your deepest philosophy.

We fear our neighbor's hostile mood because we are afraid that this mood will lead him to penetrate our secrets.

How much rationality and higher protection there is in such self-deception, and how much falseness I still require in order to allow myself again and again the luxury of my sincerity.

I can tell by my own reaction to it that this book is harmful." But let him only wait and perhaps one day he will admit to himself that this same book has done him a great service by bringing out the hidden sickness of his heart and making it visible.— Altered opinions do not alter a man’s character (or do so very little); but they do illuminate individual aspects of the constellation of his personality which with a different constellation of opinions had hitherto remained dark and unrecognizable.

Many people, especially women, never experience boredom because they have never learned to work properly.