The establishment of ethical first principles

Abstract

Sidgwick discusses the dilemma confronting the ethical theorist whose first principles, as first principles, do not require a proof, and yet are rarely accepted without a defence. The solution lies in Aristotle’s distinction between logical (or natural) priority and priority in the mind of one person. While a proposition may be self-evident, that is to say, cognizable without reference to other propositions, some rational process may be required to connect it to propositions already accepted in the mind of one individual.