  The emotivist theory of ethics had its most articulate treatment in Ethics and Language by Charles Stevenson (1908–79). Stevenson was a positivist, but also the heir of John Dewey (1859–1952) and the American pragmatist tradition. Dewey had rejected the idea of fixed ends for human beings, and stressed that moral deliberation occurs in the context of competition within a person between different ends, none of which can be assumed permanent. He criticized theories that tried to derive moral principles from self-certifying reason, or intuition, or cosmic forms, or divine commands, both because he thought there are no self-certifying faculties or self-evident norms, and because the alleged derivation disguises the actual function of the principles as devices for social action. Stevenson applied this emphasis to the competition between people with different ends, and stressed the role of moral language as a social instrument for persuasion (Ethics and Language, Ch. 5). On his account, normative judgments express attitudes and invite others to share these attitudes, but they are not strictly speaking true or false.