One thought spectra are marvellous, but it is not possible to make progress there. Just as if you have the wing of a butterfly then certainly it is very regular with the colors and so on, but nobody thought one could get the basis of biology from the coloring of the wing of a butterfly.

And anyone who thinks they can talk about quantum theory without feeling dizzy hasn't yet understood the first thing about it.

It is the hallmark of any deep truth that its negation is also a deep truth.

A physicist visits a colleague and notices a horseshoe hanging on the wall above the entrance. 'Do you really believe that a horseshoe brings luck?' he asks. 'No,' replies the colleague, 'but I've been told that it works even if you don't believe in it.'

Einstein, stop telling God what to do!

Anybody who is not shocked by this subject has failed to understand it. [of quantum mechanics]

We are trapped by language to such a degree that every attempt to formulate insight is a play on words.