The opposite of a correct statement is a false statement. Bu... - Niels Bohr

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

"An expert is a person who has made all the mistakes that can be made in a very narrow field."

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

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

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