"One of the most dangerous things for a man's mind is to be without an object."

"There is nothing more deceptive than an obvious fact."

"My mind rebels at stagnation. Give me problems, give me work, give me the most abstruse cryptogram, or the most intricate analysis, and I am in my own proper atmosphere. But I abhor the dull routine o…"

"The more bizarre a thing is the less mysterious it proves to be. It is only the commonplace that truly puzzles."

"It is a common mistake to confuse the exceptional with the impossible."