There are trivial truths and there are great truths. The opp... - Niels Bohr

"Prediction is very difficult, especially about the future."

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

"How wonderful that we have met with a paradox. Now we have some hope of making progress."

"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."

"The opposite of a correct statement is a false statement. But the opposite of a profound truth may well be another profound truth."