The value of a man resides in what he gives

I was originally supposed to become an engineer but the thought of having to expend my creative energy on things that make practical everyday life even more refined, with a loathsome capital gain as the goal, was unbearable to me.

A hundred times every day I remind myself that my inner and outer life are based on the labors of others.

I have become an obstinate heretic in the eyes of my colleagues. Momentary success carries more power of conviction than reflections upon principles.

[Kepler] had to realize clearly that logical-mathematical theoretizing, no matter how lucid, could not guarantee truth by itself; that the most beautiful logical theory means nothing in natural science without comparison with the exactest experience. Without this philosophic attitude, his work would not have been possible.

You can never solve a problem with the same kind of thinking that created the problem in the first place.

When a blind beetle crawls over the surface of a globe he doesn't notice that the track he has covered is curved. I was lucky enough to have spotted it.