David Hume — "The life of a man is of no greater importance to the universe than that of an oy…"

"The great subverter of Pyrrhonism or the excessive principles of scepticism is action, and employment, and the occupations of common life."

"When we run over libraries, persuaded of these principles, what havoc must we make? If we take in our hand any volume; of divinity or school metaphysics, for instance; let us ask, Does it contain any …"

"If we would satisfy ourselves, therefore, concerning the nature of that evidence, which assures us of matters of fact, we must enquire how we arrive at the knowledge of cause and effect."

"Whatever is may not be, and whatever is not may be."

"The chief spring or actuating principle of the human mind is pleasure or pain."