Historical development: from noncognitivism/emotivism to cognitivist expressivism
Some early versions of expressivism arose during the early twentieth century in association with
logical positivism. These early views are typically called "
noncognitivist".
A. J. Ayer's
emotivism is a well-known example. According to emotivism, the act of uttering a moral sentence of the type "X is good (bad)" is closely akin to the expression of a positive (or negative) emotional attitude toward X, and such an utterance can be paraphrased by "Hurrah for X!" or "Boo, X!"
C. L. Stevenson also advanced an important version of emotivism. At the beginning of the middle of the twentieth century,
R. M. Hare was an important advocate of expressivism / noncognitivism. Hare's view is called
prescriptivism because he analyzed moral sentences as universal, overriding prescriptions or imperatives. A prescriptivist might paraphrase "X is good" as "Do X!". More recent versions of expressivism, such as
Simon Blackburn's "
quasi-realism",
Allan Gibbard's "norm-expressivism", and Mark Timmons' and Terence Horgan's "cognitivist expressivism" tend to distance themselves from the "noncognitivist" label applied to Ayer, Stevenson, and Hare. What distinguishes these "new wave" expressivists is that they resist
reductive analyses of moral sentences or their corresponding psychological states, moral judgments, and they allow for moral sentences/judgments to have truth value. Horgan and Timmons' label "cognitivist expressivism" in particular captures the philosophical commitment they share with Blackburn and Gibbard to regard moral judgments as cognitive psychological states, i.e.
beliefs, and moral sentences as vehicles for genuine assertions or truth-claims. Much of the current expressivist project is occupied with defending a theory of the truth of moral sentences that is consistent with expressivism but can resist the Frege-Geach objection (see below). Expressivists tend to rely on a minimalist or deflationary
theory of truth to provide an irrealist account for the truth of moral sentences. ==Arguments for==