The Economic Thought of William Petty: Exploring the Colonialist Roots of Economics by Hugh Goodacre (review)

Sir William Petty became famous in the middle of the seventeenth century for his outsized intellect and ambition. Born in humble circumstances, he leveraged his training as a physician and academic to become the physician-general of Cromwell’s army in Ireland, then oversaw the Down Survey of Ireland, the first countrywide cadastral survey and mapping project in Europe, completed in a mere year and a half. He attained great landed wealth in Ireland, but the project of redistributing the island into English hands proved controversial, embroiling him in allegations of fraud.

Following the Restoration, when Parliament lost control of the country to the Stuarts, Petty spent much of his life attempting to regain the political influence that he had enjoyed under the leadership of the Cromwells. While he engaged in a variety of scientific projects, such as the design and promotion of catamarans, he focused his intellectual energy primarily on “political arithmetic” (195–96), the attempt to quantify the economic situation of England and its colonies to maximize the state’s power and wealth. In the Down Survey, he had already used mathematics to accomplish a most unlikely task, and he did not deign to limit his proposals to the politically possible. For example, his vision for Ireland included a population transfer scheme in which the government would evict most of the Irish to England, making way for efficient ranches.

Although his constant scheming never found favor with either Charles II or James II, Petty became friends with William Penn. The two discussed Petty’s ideas for efficient colonization and Petty became one of the first investors in the province. His Irish surveys formed the theoretical basis for Pennsylvania’s land distribution system.

Much of what Petty wrote would today be classified as economics, and a variety of historians of economic thought have noted Petty’s importance as perhaps the preeminent seventeenth-century English economist, setting the foundation on which the likes of Adam Smith and David Ricardo would build classical economics. For example, economist Guy Routh attributed to Petty, “the labour theory of value; surplus value; differential rent; the theory of interest; the distinction between price and value; the role of monopolies; velocity of circulation; the multiplier; natural law; national accounting; division of labour and economies of scale; [and] public works as a remedy for unemployment” (1).

Hugh Greenacre’s The Economic Thought of William Petty: Exploring the Colonialist Roots of Economics is not a blow-by-blow account of Petty’s economics. Instead, Greenacre seeks to place Petty’s ideas in their proper historical context. Because Petty is remembered today as a steppingstone for more highly regarded economists, Goodacre argues that historians of economic ideas have ignored the historical context in which he developed his theories. Committed to the colonial project of Ireland, Petty designed his economic analysis and proposals to enhance not Ireland and its people, but England, the English, and the metropole of London. It is therefore problematic that Petty’s ideas, laid out in the service of an expansionist England, still provide the core logic for developmental economics, which is primarily intended to benefit independent postcolonial nations. As Goodacre writes, “questions inevitably arise as to the level of self-awareness prevailing in the subdiscipline regarding the intellectual roots of the conceptual apparatus on which its practitioners continue to rely” (37).

Goodacre arranges his discussion of Petty thematically. He presents a brief biography of Petty and an overview of how economic historians view his status, going into detail on Petty’s time in Ireland and how his experiences there influenced his views. He explains the basis of Petty’s economics, which were rooted in his view of England as a fiscal-military state. This is in contrast to historians of economic thought who have portrayed Petty’s motives as “philanthropic and pacific . . . to represent the intellectual roots of economics in as favourable a...