"It has been said that man is a rational animal. All my life I have been searching for evidence which could support this."
"Many people would sooner die than think; In fact, they do so."
"The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts."
"What the world needs is not dogma but an attitude of scientific inquiry combined with a belief that the torture of millions is not desirable, whether inflicted by Stalin or by a Deity imagined in the likeness of the believer."
"Not to be certain is, I think, one of the essential things in rationality."
"Man is a credulous animal, and must believe something; in the absence of good grounds for belief, he will be satisfied with bad ones."