“Never express yourself more clearly than you are able to think”

“No, no, you're not thinking; you're just being logical.”

“Every great and deep difficulty bears in itself it’s own solution. It forces us to change our thinking in order to find it.”

“There are some things so serious that you have to laugh at them.”

“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.”

“Prediction is very difficult, especially about the future.”