Adam Smith's Debts to Nature

Adam Smith (1723–90) was the towering figure of Enlightenment political economy, a stature he attained in his own lifetime much as Sir Isaac Newton had in his. The secondary literature on Smith is enough to sink a small boat; there are more than 1,000 books and journal articles.¹ Unfortunately, or perhaps fortunately, most of these are Whiggish efforts to show just how modern Smith was in his economic analysis. As Jacob Viner (1991, 92) once remarked, "An economist must have peculiar theories indeed who cannot quote from the Wealth of Nations to support his special purposes." Such versatility has lent itself to considerable abuse among modern economists in search of venerable ancestry.

Smith, however, did not view himself as an economist. Indeed, the English term was not in common usage at the time.² Smith was a professor of logic and moral philosophy, with a wide range of interests, including jurisprudence, natural philosophy, rhetoric, and belles lettres. Although we have reason to believe that he wrote voluminously, he only shepherded two books into print, the Theory of Moral Sentiments (1759) and the Wealth of Nations (1776).³ Both were revised substantially throughout his remaining years. Smith lived to see the sixth edition of his first book appear just weeks before he died, and the sixth edition of the second was published in the following year. For Smith, the Theory of Moral Sentiments was the more significant of the two, but it waned from the philosophical firmament after Immanuel Kant and, while increasingly appreciated, has yet to regain canonical standing.⁴

As numerous scholars have argued, natural and moral philosophy were closely joined by philosophers of the Scottish Enlightenment, arguably more so than in France or northern Europe.⁵ Smith, needless to say, was a shining example of this felicitous union. He took up Newton's challenge to extend his rules of reasoning into uncharted land and was regarded by others, such as John Millar and Thomas Pownall, as "the Newton of the moral sciences" (see Redman 1997, 208–15). My objective here is to adumbrate Smith's indebtedness to concepts rather than methods of early modern natural philosophy. Some of the many topics in Smith's economics where nature rears its head are labor, markets, and the pursuit of wealth.

1. Smith's Knowledge of Natural Philosophy

We know that Adam Smith was well versed in classics, mathematics, and natural philosophy, a grounding he received first in Scotland, at his local school and at the University of Glasgow (1737–40), and then, to a lesser degree, at Oxford (1740–46). His most influential teacher was Francis Hutcheson, who served as professor of moral philosophy at Glasgow but who also had a solid grounding in logic and natural philosophy, including Newtonian physics. Hutcheson was known for promoting the methods of Newton in other fields and is credited with inspiring Smith for doing just that in moral philosophy. One of the more memorable courses Smith took from Hutcheson was on the subject of "Pneumaticks," by which was meant the "science of spirits or spiritual beings" (Ross 1995, 43). What little evidence we have of the course suggests that Hutcheson treated the subject as speculative physics (see Moore and Silverthorne 1983). It covered metaphysical questions about ethereal beings as well as the new physics of airs and other elastic fluids.

Smith also took courses from Robert Dick on experimental physics, a subject that was much emphasized in the Glasgow curriculum. According to Ian Simpson Ross (1995), the Scottish universities were keen to be "modern" and thus keep abreast of recent innovations in experimental natural philosophy, unlike the more traditional curriculum at Oxford.⁶ An additional fee of three shillings per session was levied on each student to fund the purchase of equipment. While some equipment had been acquired in the late seventeenth century, the collection was mostly developed in the early to mid...