The very nature of the quantum theory ... forces us to regard the space-time coordination and the claim of causality, the union of which characterizes the classical theories, as complementary but exclusive features of the description, symbolizing the idealization of observation and description, respectively.
Niels BohrThe best weapon of a dictatorship is secrecy, but the best weapon of a democracy should be the weapon of openness.
Niels BohrIf anybody says he can think about quantum physics without getting giddy, that only shows he has not understood the first thing about them.
Niels BohrThose who are not shocked when they first come across quantum theory cannot possibly have understood it.
Niels Bohr