For Millar, different historical stages were not just distinct but progressive: “There is … in human society, a natural progress from ignorance to knowledge, and from rude to civilized manners, the several stages of which are usually accompanied with peculiar laws and customs” (<4>). Each succeeding stage satisfies needs in a prior stage while developing new needs and the means to satisfy and express them through science (“knowledge”) and art (“civilized manners”). Stages were also progressive in another sense: our present stage of commerce has far less brutality than the first stage and less romantic extravagance than the later stages and thus allows women to be “more universally regarded upon account of their useful or agreeable talents” (<89>). Millar clearly viewed the unbigoted meritocracy and personal liberty appropriate to the fourth stage of society as desirable, and slavery and domestic tyranny as inappropriate to a progressive society insofar as it thwarted liberty and merit. In other words, unlike Rousseau and like Smith and Hume, Millar considered liberty and equality to be social achievements:11
Whereever men of inferior condition are enabled to live in affluence by their own industry, and, in procuring their livelihood, have little occasion to court the favour of their superiors, there we may expect that ideas of liberty will be universally diffused. This happy arrangement of things is naturally produced by commerce and manufactures; but it would be as vain to look for it in the uncultivated parts of the world, as to look for the independent spirit of an English waggoner among persons of low rank in the highlands of Scotland. (<241–42>)
This stress on progress was not an unbridled advocacy of wealth. Much like Smith, Millar viewed stagnant luxury as a dangerous corruptor of morals that stopped “useful and agreeable” talents from being recognized.12 Wealth is desirable only insofar as it gives rise to liberty and historical progress.
The scientist of human nature arrives at regularities that differentiate these stages through cross-cultural and comparative historical study. Millar’s conclusions were tempered by the circumspect attitude toward evidence that he had learned from Hume.13 In the later chapters of Ranks on government he made much use of Montesquieu’s comparisons of legal codes and constitutions in The Spirit of the Laws. But Millar presumed, following Hume and contra Montesquieu, that mores or “moral causes,” as opposed to physical causes such as climate, are responsible for characteristic differences in human population. Customs and mores arise from the aggregate actions of individuals. But individuals differ widely in their behavior, and the comparison of a few human individuals is not sufficient to educe general rules of human nature. By comparing many individuals, or different societies composed of many individuals, one can find consistent patterns of behavior. And by comparing regularities across historical periods the human scientist can discern stadial differences determined by underlying causes in human nature.
The stadial analysis had a further important function. It presupposed no particular contingent historical narrative such as “the Goths invaded,” “Watt discovered the steam engine.” Consequently, the “Age of Hunters” was not a particular time or place but rather a social arrangement built around a mode of subsistence that had existed, and perhaps would exist, in many times and places. Thus the divide between “ancients and moderns” that fascinated thinkers like Hume in the first half of the eighteenth century and continued to interest many thinkers who promoted comparative stadial history—such as Kames, Monboddo, and Gilbert Stuart—was moot. Instead, history has a scientifically accessible structure with identifiable moral causes.
This does not mean that stages necessarily follow one another like clockwork. Rome declined because of excess luxury and the accidental cause of the barbarian invasions (<218–19>). Accidents enter into the forms of particular governments as well. For example, Solon’s and Lycurgus’s idiosyncrasies were partially responsible for the very different manners of Athens and Sparta. But for laws to have influence with the people whom they are to govern, they must harmonize with and speak to existing regularities. The scientist of human nature should discover these empirical regularities yet not dismiss the role of accident (<7>).14
So far this is of a piece with Hume and Smith. But Millar’s Ranks goes beyond them in providing a stadial genealogy of particular rights and showing that rights should be understood as evolving responses to human needs. By focusing on familial rights Millar brought the problem of natural rights into sharp focus. If the most basic social rights are mutable and artificial, and if man is social, what is one to make of natural rights at all? Hume had pointed the way in his analyses of property in the Treatise and of the history of love by implying that all rights are to some degree adventitious, and natural rights of the Lockean sort are highly questionable. Millar’s contribution was to push this analysis in a single-minded way within a well-worked-out historical theory.15
A comparison with Smith’s discussion of the rights of husband over wife shows Millar’s novelty. Smith taught jurisprudence through the framework of his predecessor and teacher Francis Hutcheson, building the discussion of the first of the rights “which belong to a man as a member of a family” around three aspects of marriage: “1st, the manner in which this union is entered into and the origin of it; 2dly, the obligation or rights that are thereby acquired and the injuries corresponding to these; and 3dly, the manner in which it is dissolved” (LJ (A), iii.2). Smith treated these rights historically, but the discussion was always structured by background issues in natural law: the standing of polygamy, the perpetuity of marriage, the reasons for dissolving a marriage. The primary purpose of Smith’s lectures was to elucidate marriage; the historical evolution of marital rights was auxiliary. Similarly, Smith’s very brief discussion of the right of father over children centered on the issue of greatest interest to natural lawyers: patria potestas.
Smith’s discussions of the rights of the master and, most notably, the rights of the community member or citizen involve much more extensive stadial comparison. He used comparisons between societal stages to make a normative claim, “that the state of slavery is a much more tolerable one in a poor and barbarous people than in a rich and polished one” (LJ (A), iii.105), and he developed a complex stadial history of governments as well (iii.105-v. 43), both of which influenced the Ranks. Unlike Smith, however, Millar treated each of the rights directly through the stadial theory and showed how changes in the scope of the right arose from changing needs. We have seen this with the right of husband over wife; Millar made parallel arguments for the other three rights under consideration. Furthermore, he attempted to draw normative consequences about authority itself. Slavery and brutality toward inferiors have no place in progressive societies because authority has legitimacy when it is used to efficiently satisfy needs. The authority appropriate to an adventitious right in a particular historical stage ought to be limited by the useful and agreeable ends that the rights allow human groups to fulfill. Once a right gets in the way of the satisfaction of these needs, for example, by stopping useful and agreeable talents of women from being recognized, it is no longer legitimate. With this insight Millar had created a fully empirical moral theory centered on adventitious rights and allowing for normative criticisms.
John Craig’s “Account of the Life and Writings of the Author”
Ranks is an important work of empirical moral philosophy, and the fourth, posthumous edition