In his Treatise, Hume refers to "a progress of the sentiments" (Book III, Sec. II). As I understand this, he takes it that we may develop a bona fide commitment to justice such that it can supplement or even contravene the private interests that originally gave rise to it (i.e., justice being a product of artifice). I take him to be making an ontological claim here rather than a historical one, particularly as he appears to regard our “suppos’d state of nature” as "mere philosophical fiction". Is there an alternate interpretation?