I always found I was in the best of company, alone.

The more I learn, the more I realize I don't know.

The most important method of education always has consisted of that in which the pupil was urged to actual performance.

I was just more stubborn and more passionate than most about physics.

If one day you have to choose between the world and love, remember this: If you choose the world you’ll be left without love, but if you choose love, with it you will conquer the world

The opinion prevailed among advanced minds that it was time that belief should be replaced increasingly by knowledge; belief that did not itself rest on knowledge was superstition, and as such had to be opposed.

Time flies when you are having fun.