 The solution, Hume argues, is that we naturally fall into a “convention” by which we observe that rules of property — the observance of which is key to the virtue of justice — is good for all of us. This convention is no formal agreement; Hume argues that it cannot be something like the product of promise or compact (T III.ii.II). Instead, “it arises gradually, and acquires force by a slow progression, and by our repeated experience of the inconveniences of transgressing it” (T III.ii.II, p. 490). Much as two men pulling the oars in a boat together need no explicit agreement to find they prosper by such an arrangement, so do we generally. (Wilson 2018 explores support for Hume’s hypothesis through work in experimental economics.) So in the end it is self-interest that drives us to comply with the requirements of justice, though Hume adds that sympathy with the public interest induces our endorsement of it once justice has become established. This endorsement, however, is reserved for a scheme of property rules taken generally; as Hume observes, individual instances of compliance may frequently be “contrary to public interest,” though such compliance is still required of us. Hume believes the benefit of the system overall, both to society and to individual, requires that rules not admit of exceptions (T III.ii.II, E Appendix III, §256). Self-interest accounts for the possibility of our being motivated to act as the virtue of justice requires, and both the utility and the agreeableness, both to ourselves and others, of a resulting social order with respected property rules, leads to our approbation of that motivation as a virtue. 