  According to the dominant twentieth-century interpretation, Hume says here that no ought-judgment may be correctly inferred from a set of premises expressed only in terms of ‘is,’ and the vulgar systems of morality commit this logical fallacy. This is usually thought to mean something much more general: that no ethical or indeed evaluative conclusion whatsoever may be validly inferred from any set of purely factual premises. A number of present-day philosophers, including R. M. Hare, endorse this putative thesis of logic, calling it “Hume’s Law.” (As Francis Snare observes, on this reading Hume must simply assume that no purely factual propositions are themselves evaluative, as he does not argue for this.) Some interpreters think Hume commits himself here to a non-propositional or noncognitivist view of moral judgment — the view that moral judgments do not state facts and are not truth-evaluable. (If Hume has already used the famous argument about the motivational influence of morals to establish noncognitivism, then the is/ought paragraph may merely draw out a trivial consequence of it. If moral evaluations are merely expressions of feeling without propositional content, then of course they cannot be inferred from any propositional premises.) Some see the paragraph as denying ethical realism, excluding values from the domain of facts.