"Every thing in the world is purchased by labour."

"The most perfect philosophy of the natural kind is of little use to us, if it do not enable us to correct our errors, and regulate our passions."

"I am apt to suspect the negroes and in general all other species of men (for there are four or five different kinds) to be naturally inferior to the whites."

"The life of man is a perpetual flux of motion. All his thoughts, sentiments, and actions are in a continual succession, and never remain for any considerable time in the same state."

"We make allowance for a certain degree of selfishness in men; because we know it to be inseparable from human nature, and inherent in our frame and constitution."