Who said “In order to shake a hypothesis, it is sometimes not necessary to do anything more than…”?

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

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

“No theory is good unless it permits, not rest, but the greatest work. No theory is good except on condition that one use it to go on beyond.”

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

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

“Good music is very close to primitive language.”

“There is only one passion, the passion for happiness.”

“Poetry must have something in it that is barbaric, vast and wild.”

“The blood of Jesus Christ can cover a multitude of sins, it seems to me.”

“All abstract sciences are nothing but the study of relations between signs.”

“It is not human nature we should accuse but the despicable conventions that pervert it.”