Never express yourself more clearly than you are able to think.

If anybody says he can think about quantum physics without getting giddy, that only shows he has not understood the first thing about them.

All rising curves that show unwelcome trends in human affairs will approach infinity if extended far enough, but it is we who dictate the curve and not vice versa.

Prediction is difficult, especially the future.

If you think you understand it, that only shows that you don't know the first thing about it.

Those who are not shocked when they first come across quantum theory cannot possibly have understood it.

Our task is not to penetrate the essence of things, the meaning of which we do not know anyway, but rather to develop concepts which allow us to talk in a productive way about phenomena in nature