The term “private will” is rarely used nowadays except in scholarly discussions of Rousseau. Nevertheless, what it designates pervades moral, social, and political theory. As remarked, even those who would concede the existence of the general will, the private will's rival in the Rousseauean scheme, believe that it has little, if any, applicability in political contexts. On the other hand, the reality and applicability of private volition are beyond dispute. I have suggested that this understanding is partly a consequence of a lingering inclination to consider individuals to be relevantly like radically independent atoms. But the idea that the private will is unproblematic and ubiquitous is also encouraged by more direct confusions.

Individuals moved by private wills seek, insofar as they are rational, to do as well for themselves as they can. This claim appears innocuous. But we have seen that it is ambiguous and potentially misleading. It is also contrary to the views of virtually all moral philosophers before Hobbes. Practical reason, on the formerly dominant view, was substantive, not just instrumental; rationality concerned the ends individuals' willed much more than the adequacy of the means they adopted. To be sure, some philosophers along with theologians and moralists continue to resist instrumentalist accounts of practical reason. Still, the idea that rationality is a matter of advancing one's own interests (where “interest” is a placeholder term, awaiting substantive elaboration) is so seldom disputed nowadays – and so integral to the tradition of economic modeling in contemporary social and political theory – that it has effectively become part of common sense.