What is the nature of authority? How does it change and why? The Origin of the Distinction of Ranks is John Millar’s¹ concise but trenchant answer to these questions via an empirical analysis of three so-called adventitious² personal rights and one adventitious “governmental right” of natural law theory: the right of husband over wife, father over children, master over servants, and chief or sovereign over tribesmen or citizens. These rights are of obvious interest for a social philosopher since all have a degree of authority built into them—the right of the father over the child, for example, presumes the father’s authority to appropriately discharge his role and the duties incumbent to it. Yet, when these four rights are examined comparatively and historically, from Aragon to Zeeland, from ancient Rome to Georgian Glasgow, drastic differences appear in the authority appropriate to the exercise of the right. And this is not just a problem of comparing European and non-European societies. The Roman law, the backbone of much European legal and moral thinking, allowed the head of the household to treat wife, children, and servants as property and to expose infants.³ The authority appropriate for the exercise of the right by early Romans (and Greeks) is completely at odds with the authority proper to a progressive eighteenth-century society. Millar’s Ranks provides an empirical account of how rights arise and how they change, and a means to understand historical discrepancies in the scope of authority. It also attempts to draw some limited normative consequences and thus offer the elements of an empirical moral theory.

      The Argument of the Ranks

      It is not surprising that the Ranks turns on rights, considering that the three most important influences on Millar’s thinking all stressed that evolving systems of justice and rights were the backbone of morals and human nature. In Treatise III.2 David Hume argued that justice is an artificial human creation that guides and serves human utility. In his seminal essay, “The Rise and Progress of the Arts and Sciences,” Hume discussed the history of the authority of husband over wife—the subject of the first long section of the Ranks—as an index of the progress of manners in society.⁴ Adam Smith presented his historical theory of justice and rights in a series of lectures on moral philosophy that Millar attended in 1751. Student transcripts from Smith’s lectures from the 1760s include extensive treatment of the rights Millar later considered in the Ranks, rooted in a stadial division between the ages of “Hunters,” “Shepherds,” “Agriculture,” and “Commerce.”⁵ Lord Kames treated the historical evolution of different aspects of the law, including criminal law and property law, in his Historical Law-Tracts (1758), connecting legal obligation, moral duty, and social progress.⁶

      Justice, law, and rights were also central to Millar’s pedagogy. When the first edition of the Ranks appeared in 1771—Observations Concerning the Distinction of Ranks in Society—Millar had held the Regius Chair of Civil Law at the University of Glasgow for ten years. His primary teaching duty had been lecturing on Justinian’s Institutes and Digest with the aid of Heineccius’s commentaries.⁷ The combination of Smith’s jurisprudence and variations in rights within the Digest itself—for example, changes in the Roman peculium (Ranks, <132–33>)—must have set Millar thinking about the history of adventitious rights. Furthermore, in addition to his regular course Millar undertook a series of “private” “Lectures on Government.” These lectures, which he continued for the rest of his life, were the source of his two major works: the Ranks and the Historical View (see appendix 3). Given the connection between the government lectures and the course on Roman law, it is unsurprising that the Ranks—the first part of the “Government” course—is infused with justice and rights.

      The Ranks’s treatment of rights and their order was likely derived from Smith; likewise the division of human history into the four “ages” distinguished by population, wealth, the needs these engendered, and the ways those needs were satisfied.⁸ Man’s earliest stages were characterized almost wholly by attempts to satisfy simple needs. As basic needs were satisfied more efficiently and population grew, wealth resulting from the satisfaction of needs allowed for leisure, the rise of human institutions, and more complex desires—the arts and sciences, taste, and love.

      Romantic love provides a good illustration of how successive stages multiply needs. In the earliest stages of mankind commerce between the sexes was a ubiquitous function of animal need and so considered of little import in comparison with the acquisition of food (<28>). When men moved to the pastoral stage, food supplies became more regular and the labor in acquiring them less:

      The leisure, tranquillity, and retirement of a pastoral life, seem calculated, in a peculiar manner, to favour the indulgence of those indolent gratifications … and mere animal pleasure is more frequently accompanied with a correspondence of inclination and sentiment. (<58>)

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