ABSTRACT
Sir William Petty's chief role in Irish history is easily summarised: following Cromwell's reconquest of Ireland, Petty designed and oversaw the 'Down Survey', enabling the massive expropriation of Catholic-owned land in the Cromwellian settlement. Petty, Political Anatomy - it is possible to read '1/2 the said women' as referring to half of the 'two thousand per Annum' who become 'unmarried marriageable Women', rather than to half of the total population of 20,000 'unmarried marriageable Women'. A different Petty animates the historiography of social science. This is the creator of 'political arithmetic', an entity variously interpreted as an early form of economic analysis, a proto-statistical demography, quantitative, bureaucratic rationality. By emphasising Petty's role in the land settlement, historians of Ireland have underestimated his political arithmetic's roots in, and implications for, Irish politics during the 1670s and 1680s. The exchange of women would prevent a generation of poor Irish men from marrying poor Irish women, substituting English brides in their place.
