A deep truth is a truth so deep that not only is it true but it's exact opposite is also true.

Some things are so serious, they can only be joked about.

When it comes to atoms, language can be used only as in poetry.

Rutherford is a man you can rely on; he comes regularly and enquires how things are going and talks about the smallest details - Rutherford is such an outstanding man and really interested in the work of all the people around him.

We depend on our words... Our task is to communicate experience and ideas to others. We must strive continually to extend the scope of our description, but in such a way that our messages do not thereby lose their objective or unambiguous character... We are suspended in language in such a way that we cannot say what is up and what is down. The word "reality" is also a word, a word which we must learn to use correctly.

Every sentence I utter must be understood not as an affirmation, but as a question.

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