"The most perfect philosophy of the natural kind only staves off our ignorance a little longer: as perhaps the most perfect philosophy of the moral or metaphysical kind serves only to discover more ope…"

"All human life must perish, were his principles to prevail. All discourse, all action would immediately cease, and men remain in a total lethargy, till the necessities of nature, unsatisfied, put an e…"

"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."

"I am sensible that my philosophy is very little susceptible of the ornaments of eloquence and poetry."

"The general maxims of morality are insufficient to determine us to action."