You can recognize a small truth because its opposite is a falsehood. The opposite of a great truth is another truth.

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

When asked ... [about] an underlying quantum world, Bohr would answer, 'There is no quantum world. There is only an abstract quantum physical description. It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about Nature.'

Einstein, stop telling God what to do!

When we measure something we are forcing an undetermined, undefined world to assume an experimental value. We are not measuring the world, we are creating it.

No, no, you're not thinking; you're just being logical.

One must always do what one really cannot.