Who said “No theory is good unless it permits, not rest, but the greatest work. No theory is good…”?

“Theories that go counter to the facts of human nature are foredoomed.”

“In order to shake a hypothesis, it is sometimes not necessary to do anything more than push it as far as it will go.”

“Delight at having understood a very abstract and obscure system leads most people to believe in the truth of what it demonstrates.”

“A young man is a theory, an old man is a fact.”

“It is theory that decides what can be observed.”

“A straight path never leads anywhere except to the objective.”

“The abominable effort to take one's sins with one to paradise.”

“It is better to be hated for what you are than to be loved for what you are not.”

“The sole art that suits me is that which, rising from unrest, tends toward serenity.”

“Man is more interesting than men. God made him and not them in his image. Each one is more precious than all.”

“The most decisive actions of our life -- I mean those that are most likely to decide the whole course of our future -- are, more often than not, unconsidered.”