 What Hume wants to show is, first, that we can have such a disposition or quality (that is, that it is possible for us to have a quality or character to observe the rules of justice), and, second, that such a quality would count as a virtue, given his criteria. His approach to these questions in the Treatise is framed by a problem he has set up himself. To appreciate that problem, we have to step back to Hume’s broader view about moral motivation. Hume had argued that moral principles “are not conclusions of our reason” (T III.i.I); instead, they are “more properly felt than judg’d of” (T III.i.II). Morality, and virtue, is a matter of sentiments or passions. Why? Hume marshals a number of arguments to this effect which are not relevant to our purposes. The basic reason is that the functional roles of reason and the passions are markedly different, in Hume’s view. The task of reason is to discover truth or falsehood, in “relations of ideas” or “matters of facts” (T III.i.I); as such, it utterly lacks the capacity to move us to action. Only the passions can do that (T II.iii.III). The passions, on the other hand, have no representational content whatsoever; they are “original existences” (T II.iii.III; III.i.I). Virtue is paradigmatically a practical matter: it is a property of what we do, and to act we must be motivated. That means any successful account of virtue must find it in our passions, not in any aspect of our reason (T III.i.I). So far so good.