“Parfit believes that there are true answers to moral questions, just as there are to mathematical ones. Humans can perceive these truths, through a combination of intuition and critical reasoning, but they remain true whether humans perceive them or not. He believes that there is nothing more urgent for him to do in his brief time on earth than discover what these truths are and persuade others of their reality. He believes that without moral truth the world would be a bleak place in which nothing mattered. This thought horrifies him.”

— Larissa MacFarquhar, How to be Good (The New Yorker, September 5, 2011)