“I am indebted to my father for living, but to my teacher for living well.{His teacher was the legendary philosopher Aristotle}”

“Sex and sleep alone make me conscious that I am mortal.”

“Upon the conduct of each depends the fate of all.”

“Remember, upon the conduct of each depends the fate of all.”

“There is nothing impossible to him who will try.”

“One cannot always know what children are thinking. Children are hard to understand, especially when careful training has accustomed them to obedience, and experience has made them cautious in their conversation with their teachers. Will you not draw from this the fine maxim that one should not scold children too much, but should make them trustful, so that they will not conceal their stupidities from us?”

“As to your Newton, I confess I do not understand his void and his gravity; I admit he has demonstrated the movement of the heavenly bodies with more exactitude than his forerunners; but you will admit it is an absurdity to maintain the existence of Nothing.[Letter to Voltaire, 25 Nov. 1777]”