"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."
"You can recognize a small truth because its opposite is a falsehood. The opposite of a great truth is another truth."
"There are trivial truths and there are great truths. The opposite of a trivial truth is plainly false. The opposite of a great truth is also true."
"How wonderful that we have met with a paradox. Now we have some hope of making progress."
"The opposite of a correct statement is a false statement. But the opposite of a profound truth may well be another profound truth."
"Prediction is very difficult, especially about the future."