When it comes to talking about practical reasoning, “Humean” is a synonym for “instrumentalist.” That is, a “Humean” view of practical reasoning is one on which only means-end reasoning directed towards satisfying antecedently given desires counts as practical reasoning at all. Witness, for instance, Michael Smith's fairly recent paper, “The Humean Theory of Motivation,” which advances just this view; Smith, who does not discuss Hume himself, simply takes it for granted that the label “Humean” fits. It wasn't always this way: when Aurel Kolnai, some years back, wished to criticize instrumentalism, he described the view as Aristotle's, an attribution that would be unlikely now.

Why care about a name? There are two reasons. First, if any theory of practical reasoning today deserves to be considered the received view, it is instrumentalism. Calling it Hume's not only gives it the cachet that comes of association with a distinguished member of the philosophical pantheon, but invokes in its favor the arguments – and the rhetoric – Hume produces in the Treatise. Arguments for instrumentalism are hard to come by, but the lack is perhaps less urgently felt than it might be because it is assumed that Hume's arguments are already on hand. Second, the label gets in the way of reading Hume, and so obscures our vision of a characteristically ingenious and subtle philosophical mind: if we know what Humeanism is, and we consequently think we know what Hume thought, we are much less likely to see, and learn from, what he actually did think.