“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.”

“I survive by finding the sweet spot between reason and unreason, between the rational and irrational.”

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

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

“The basic stimulus to the intelligence is doubt, a feeling that the meaning of an experience is not self-evident.”

“Make a spurious division of one process into two, forget that you have done it, and then puzzle for centuries as to how...”

“A point of view can be a dangerous luxury when substituted for insight andunderstanding.”

“All things must be examined, debated, investigated without exception and without regard for anyone's feelings.”