Here is Foot contra @Banno, very similar to what we have been saying. My bolding:
To identify the common characteristic of the apparently somewhat diverse moral philosophies that I have just grouped together, and also to do justice to them, it will be good to start by asking how the whole non-cognitivist business began. One finds its deepest roots in David Hume. But more immediately, Ayer and Stevenson’s emotivism, like Hare’s prescriptivism, came into being as a result of the ‘linguistic turn’, popularized by logical positivism but developing far beyond it. For with ‘linguistic philosophy’ came the idea of explaining the singularity of moral judgement in terms of a special use of language, called ‘evaluation’ but more akin to exclamation and command than to anything one would normally mean by that term. With this idea it seemed possible, at last, to say clearly what G. E. Moore had meant, or should have meant, when he insisted that goodness was a special kind of ‘non-natural’ property.[2] In the development of emotivism and prescriptivism the idea of a special (‘non-natural’) property was replaced by that of a special and essentially practical use of language. And this, it seemed, was a great discovery. The language of evaluation was ‘emotive’. It expressed a speaker’s feelings and attitudes, as well as inducing similar feelings and attitudes in others. Those who had these ‘attitudes’ ‘favoured’ the things they called ‘good’: the idea of an attitude being linked to a tendency to act. Such also was Ayer’s doctrine; and a little later Hare tied ‘evaluation’ even more closely to individual action, in his theory of universalized imperatives by which a speaker exhorted others and, in the acceptance of a first-person imperative, committed himself to choose what he called ‘good’. So ‘prescriptivism’—a distinctive version of the doctrine that I have in my sights—was added to the emotivism with which it had started out.
[…]
I shall come back to [Hare’s] definition later on. First, I should say something more general about the theories I am attacking. It is characteristic of those I have mentioned and others inspired by them to suggest that the making of any sincere moral judgement requires the presence of individual feeling, attitude, or intention, and thus goes beyond ‘description’ or ‘assertion of fact’. It was recognized, of course, that the language contains many terms like ‘courage’ or ‘justice’ designed for description as well as moral judgement, but it was said that their ‘descriptive’ content could not reach all the way to moral evaluation; the speaker’s feelings or commitments to action would have to be added if evaluation were to be on the scene. Hence the apparently unquestionable distinction between ‘descriptive’ and ‘evaluative’ language, more or less taken for granted in much of contemporary ethics.
Philippa Foot, Natural Goodness, 6-7 (introduction)