“Civilization advances by extending the number of important operations which we can perform without thinking of them. ”

“It is a profoundly erroneous truism that we should cultivate the habit of thinking of what we are doing. The precise opposite is the case. Civilization advances by extending the number of important operations which we can perform without thinking about them.”

“The point about zero is that we do not need to use it in the operation of daily life. No one goes out to buy zero fish.”

“We cannot think first and act afterwards. From the moment of birth we are immersed in action and can only guide it by taking thought.”

“The ideas of Freud were popularized by people who only imperfectly understood them, who were incapable of the great effort required to grasp them in their relationship to larger truths, and who therefore assigned to them a prominence out of all proportion to their true importance.”

“We think in generalities, but we live in detail. To make the past live, we must perceive it in detail in addition to thinking of it in generalities.”

“Everything of importance has been said before by somebody who did not discover it.”