GRAUNT, JOHN

(1620–1674)

John Graunt was the author of the first quantitative analysis of human populations, Natural and Political Observations (1662). Widely acclaimed in Graunt's time, the Observations charted the course of vital and social measurement for the next century and a half, laying the basis for the emergence of demography and statistics in the nineteenth century.

Graunt cut an unusual figure among the scientific literati of his time. A London merchant who lacked higher education and was not versed in the natural sciences and algebra, he became a charter member of the Royal Society. His analyses relied on simple ratios, proportions, and odds and adhered closely to religious and political conventions in which a population's size and strength were considered to reflect a king's ability to govern in accordance with natural and God-given symmetries. However, Graunt's work also showed a keen awareness and originality with respect to contemporary scientific and rhetorical method and made implicit use of probabilistic concepts that were familiar at that time only to a small mathematical elite.

Graunt interpreted the old symmetries of the macrocosm and the microcosm in a new way: If human society has an inherent order of the kind that is supposed to characterize all natural or God-given phenomena, it should be possible to observe quantitative regularities in society that are similar to those a natural historian measures. The bills of mortality kept by London parish clerks provided Graunt with an extensive enumeration with which to explore this idea.

His search for quantitative regularities in a body of social data was without precedent and, as David Glass (1963) remarked, is characteristically statistical. Graunt, of course, knew nothing about those later developments. His method was a synthesis of three sources. The first was the philosopher Francis Bacon's (1561–1626) procedure for compiling natural histories: Graunt first ascertained that the bills were reasonably accurate compilations based on direct observation; he then compiled tables, grouping his observations to allow readers to check his logic and make their own observations. In cases where the bills appeared irregular, he examined and if necessary reclassified them to ensure consistency.

Graunt went beyond Bacon in employing his second methodological source–the arithmetic checks and balances of merchant bookkeeping–as a system to specify inherent natural regularities. Many of the measures he devised on this basis became fundamental to demography (e.g., rates of infant and child mortality, the imbalance of sex ratios at birth, crude vital rates presented as time series). The conception of population Graunt employed, however, remained basically a merchant's pragmatic notion of an accompt: Flows of births, deaths, and migrations are dealt with in an ad hoc manner rather than being related to a total population in a mathematically consistent way.

Graunt's third methodological source reflects the dual purpose of his observations as both natural and political: Each problem he addresses is treated as an exercise in political language as well as in what his contemporary, the economic writer William Petty (1623–1687), called "political arithmetic." A succession of proportions is built up persuasively in his text that demonstrate the capacities of the body politic; Graunt's book is a veritable compendium of exempla that show how to construct arithmetic arguments according to the methods used in influential rhetoric textbooks of the early seventeenth century.

Graunt's impressive arguments gave his work two enduring paths of influence. His ratios became the subject of political arithmetic as it was pursued by Petty and other economic writers like Gregory King (1648–1712) as well as many political, medical, and religious writers of the eighteenth century. This tradition, although unable to introduce major technical advances beyond Graunt's arithmetic and much less attentive to or effective in its powers of persuasion, increased awareness of the usefulness of enumerations in an era when such methods were subjects of popular suspicion.

Analytic development followed from one of Graunt's inventions that proved to be of deeper significance than he realized. Graunt's estimate of the number of "fighting men" (i.e., for London's defense) relied on a hypothetical table of mortality by age. Mathematicians interested in the nascent calculus of probabilities, such as mathematician Christian Huygens, astronomer Edmund Halley, and philosopher and mathematician Gottfried Leibnitz (1646–1716), quickly recognized in his reasoning a more general logic for calculating life expectancy. Although Graunt had not employed his table for that purpose, their analyses gave rise to the first abstract model of population: the life table.

The approach to longevity that Graunt inspired remained the only data-based social phenomenon that mathematicians could use to explore probability for over a century. By the early nineteenth century life tables had become the first formal models guiding state finance and corporate practice (in life insurance); this success shaped the data requirements of the newly established national statistical offices, enabling the ratios Graunt pioneered to be developed systematically.

See also: Demography, History of; King, Gregory; Petty, William; Population Thought, History of.

bibliography

selected works by john graunt.

Graunt, John. 1662. Natural and Political Observations Made upon the Bills of Mortality. London. Reprinted 1973 in The Earliest Classics: Pioneers of Demography, ed. P. Laslett. Farnborough, Hants, Eng.: Gregg International.

selected works about john graunt.

Glass, David V. 1963. "John Graunt and His Natural and Political Observations." Proceedings of the Royal Society, Series B, 159: 2–37.

Kreager, Philip. 1988. "New Light on Graunt." Population Studies 42: 129–140.

——. 1993. "Histories of Demography." Population Studies 47: 519–539.

——. 2002. "Death and Method: The Rhetorical Space of 17th-Century Vital Measurement." In The Road to Medical Statistics, ed. Eileen Magnello and Anne Hardy. Amsterdam: Rodopi.

Sutherland, Ian. 1963. "John Graunt: A Tercentenary Tribute." Journal of the Royal Statistical Society, Series A, 126: 537–556.

Philip Kreager