“Every sentence I utter must be understood not as an affirmation but as a question.[A caution he gives his students, to b...”

“We shall require a substantially new manner of thinking if mankind is to survive.”

“Most people would die sooner than think in fact they do.”

“In a republican nation, whose citizens are to be led by reason and persuasion and not by force, the art of reasoning bec...”

“Reason respects the differences and imagination the similitudes of things.”

“Explanations exist; they have existed for all time; there is always a well-known solution to every human problem—neat, p...”

“Doubt is an uncomfortable condition, but certainty is a ridiculous one.”

“The eye is diverted from the real business, it is caught by the spectacular action that means nothing--nothing at all.”

“We all tend to make zealous judgement, and thereby close ourselves off from revelation.”

“Thought is a strenuous art - few practice it, and then only at rare times.”

“Thinking is not to agree or disagree. That's voting.”

“False conclusions which have been reasoned out are infinitely worse than blind impulse.”