Graunt, John (1620–1674)
GRAUNT, JOHN (1620–1674)
GRAUNT, JOHN (1620–1674), English statistician and demographer. Born in London, John Graunt was the son of a draper. He was apprenticed to a haberdasher and became a successful merchant, serving as warden of the Drapers' Company in 1671–1672. He also served the city government in various capacities, reaching the level of a common councilman. Late in life, Graunt converted to Roman Catholicism; he died in 1674 at the age of 54.
Graunt's fame rest on his short book Natural and Political Observations Made upon the Bills of Mortality (1662). The book was immediately popular and went through five editions (two in the first year alone). Translations and reprints appeared throughout the eighteenth century. Because of this book, Graunt was elected fellow of the Royal Society upon direct recommendation of Charles II, an unusual honor for a London merchant. Graunt's friend Sir William Petty (1623–1687) labeled his work political arithmetic—a term that stuck throughout the eighteenth century.
Graunt was the first to analyze society numerically. Troubled by exaggerated claims about the size of London, he created methods to calculate the population from the annual numbers of christenings and burials listed in the London bills of mortality. (He reckoned London's population at 384,000, far smaller than contemporary estimates of two million.) To bring clarity to his calculations, Graunt created a series of tables. In one, he summarized the causes of death for a twenty-year period and found the mortality rates of acute and chronic diseases, especially of the plague. In another table, Graunt showed how many individuals out of a population of one hundred would be alive at specific ages. This was the first life table (or mortality table) ever constructed and was an entirely new way to conceptualize life expectancy. Mathematicians such as Edmund Halley (1656–1742) and Antoine de Parcieux refined Graunt's life table over the course of the late seventeenth and eighteenth centuries. They remain essential tools of modern demography and actuarial science.
In his analysis of the bills of mortality, Graunt identified several numerical regularities. For every fourteen males christened, for example, there were thirteen females christened; thus, there was a constant ratio between male and female births. (Graunt used this ratio to argue against polygamy.) He defined chronic diseases as those that maintained a fixed portion of the total number of burials and included in this category jaundice, gout, rickets, and, somewhat surprising, suicides. For Graunt, the prevalence of chronic diseases was a measure of the salubrity of a community. Graunt also identified a high infant mortality rate, a significant characteristic of early modern societies (one-third of all infants born died before age six).
Graunt's book laid the foundations for modern statistics and demography. His life table stimulated the application of probability mathematics to life expectancy. His use of mortality figures to evaluate the incidence and constancy of different diseases encouraged eighteenth-century physicians to apply statistics to medicine, most notably in the debates surrounding the introduction of smallpox inoculation. His efforts to provide accurate population figures spawned a tradition of political arithmetic that was only eclipsed when regular national censuses were instituted around 1800.
See also Census ; Petty, William ; Statistics .
Kreager, Philip. "Histories of Demography." Population Studies 47 (1993): 519–539.
——. "New Light on Graunt." Population Studies 42 (1988): 129–140.
Pearson, Karl. The History of Statistics in the 17th and 18th Centuries against the Changing Background of Intellectual, Scientific and Religious Thought. Edited by E. S. Pearson. London, 1978.
Rusnock, Andrea. Vital Accounts: Quantifying Health and Population in Eighteenth-Century England and France. Cambridge, U.K., 2002.
Sutherland, Ian. "John Graunt: A Tercentenary Tribute." Journal of the Royal Statistical Society, Series A, 126 (1963): 537–556.
John Graunt (1620-1674) is considered by many historians to have founded the science of demography, the statistical study of human populations. He analyzed the vital statistics of the citizens of London and wrote a book regarding those figures that greatly influenced the demographers of his day and those in the centuries that followed. Graunt was honored for his work by being made a charter member of England's Royal Society, which was composed of prominent scientists.
John Graunt was born in London, England, on April 24, 1620, to Henry Graunt, a storekeeper in Hampshire, and his wife, Mary. The eldest of seven or eight children, Graunt attended school until adolescence. At age sixteen he became an apprentice to his father, who was employed as a draper (a dealer in clothing and dry goods). In February 1641, Graunt married Mary Scott, with whom he had one son and three daughters.
As his career prospered, Graunt held several different positions in the Freedom of the Drapers' Company. He also became involved in politics and served in various jobs for the city of London, including a term as a member of London's common council. By the age of 30 Graunt had attained such influence that he was able to procure the professorship of music at Gresham College for his friend, Sir William Petty. Petty, a physician, later invented the horse-propelled military tank and was appointed surveyor general of Ireland. Like Graunt, Petty also engaged in early demographic work.
Book Based on Mortality Records
Despite his lack of formal education, Graunt became interested in mortality statistics. He got the idea to write the book that was to make him famous from having thought a great deal about the Bills of Mortality (lists of the dead) that had been published in England beginning in the late sixteenth century. His book was titled Natural and Political Observations mentioned in a following index, and made upon the Bills of Mortality With reference to the Government, Religion, Trade, Growth, Ayre, diseases, and the several Changes of the said City. The Bills of Mortality were the vital statistics about the citizens of London collected over a 70-year period. In his book, hereinafter referred to as Observations, Graunt explained that the accounts were kept as the number of deaths rose from the plague, a catastrophic illness whose germs were carried by fleas that lived as parasites on rats. In the year 1625 alone, one-fourth of England's population died, many from the plague.
According to Graunt, the recording of the London statistics "first began in the year 1592, being a time of great Mortality; and after some disuse, were resumed again in the year 1603, after the great Plague then happening likewise. These bills were Printed and Published, not only every week on Thursday, but also a general [account] of the whole Year was given in, upon the Thursday before Christmas Day. Graunt studied the statistics compiled in the Bills of Mortality, along with christening records from churches and data from an area of rural England. A practical man, he decided that these carefully collected facts could be analyzed and the results put into book form. On February 5, 1662, Graunt's newly-printed 90-page work, Observations, was distributed to the members in attendance at a meeting of England's Royal Society.
Critique of Graunt's Data Analysis
Graunt had grouped together similar facts from the 70 years of records displayed in the Bills, and noted the comparisons of findings for different population groups. From his studies he drew a number of interesting and important conclusions. Graunt modestly described his own work as "to have reduced several great confused volumes [of Bills of Mortality] into a few [easy to understand] Tables, and abridged such Observations as naturally flowed from them, into a few succinct Paragraphs, without any long series of [wordy] Deductions."
In an article on Graunt in the Dictionary of Scientific Biography, Frank N. Egerton, III pointed out that Graunt's deduction of various characteristics of populations from the data he analyzed, "indicate a good understanding of the kinds of questions that are significant for demography." But pointing out some deficiencies in Graunt's work, Egerton also wrote, "Usually [Graunt] explained his steps in solving problems, but he seldom included the actual calculations; and sometimes he omitted important information. Furthermore, his indirect approach sometimes went beyond the reliable use of his data, and the accuracy of some of his answers was difficult to evaluate."
Egerton nevertheless commended Graunt for realizing the shortcomings of his data, and pointed out that Graunt sometimes "set an excellent example by seeking verification of his estimates by different indirect methods." In addition, Egerton observed, Graunt "introduced the use of statistical samples [though he] did not pursue this subject far enough to determine the sizes of samples or means of selection needed for insuring accuracy. [Graunt] also realized that demographic procedures could be used to make projections concerning both past and future populations."
In a 1996 article in the British medical journal Lancet, Kenneth J. Rothman pointed out some of Graunt's major achievements as a pioneer demographer: Graunt was the first to publish the fact that more boys than girls are born but that the mortality rate is greater for males, resulting in the population's being almost evenly divided between males and females. Graunt reported the first time-trends for many diseases; he offered the first well reasoned estimate of London's population; he used evidence from medical records to refute the idea that plague spreads by contagion and that it occurs early during the reign of a new king; he showed that doctors have twice as many female as male patients, but that males die earlier than females; he produced early hard evidence about the frequencies of various causes of death.
Work Had Wide Influence
The invention that some historians have called Graunt's most original was his creation of "life tables"—a new way to present population and mortality statistics by calculating survivorship on a chart. Using this method Graunt was able to predict the number of persons who would survive to each successive age on his chart and the life expectancy of the groups from year to year. Development of the life tables has been hailed as marking the beginning of the science of demography. Such charts are said to have made an impact on the pioneer demographic work of other noted astronomers and scientists, including Edmund Halley (1656-1742), England's astronomer royal. The types of charts Graunt originated remain in use today.
The widspread acceptance of Graunt's work also led to his being acclaimed as the founder of the science of statistics, particularly the branch that deals with the analysis of population data. Yet Graunt never made a formal study of mathematics. Some historians have speculated that Graunt received more help with his book from his better-educated friend, William Petty (1623-1687), than is generally acknowledged. However, while Petty surely offered support to his friend and probably made some contribution to the book, most historians agree that Graunt wrote at least a major portion of the work.
Graunt's book on the Bills of Mortality had great influence throughout Europe. It has been noted that soon after its publication, France embarked on the most precise registering of births and deaths in all of Europe. The publication also caused Charles II of England to endorse Graunt's being made one of the early members of the then newly-established and prestigious Royal Society, a distinct honor for someone who was a businessman and not a professional scientist. Charles requested of the society "that if they found any more such tradesmen, they should be sure to admit them all, without any more ado."
Financial Problems and Religious Conversion
Graunt's Observations became popular reading in educated circles. On June 20, 1665, the Royal Society declared its support for the publishing of the third edition of the book, which appeared later that year. But the following year, 1666, was to bring personal disaster for Graunt. A great fire in London on September 2 destroyed his clothing firm, leaving him with financial problems that were to persist throughout the rest of his life.
During this period, Graunt converted from the Protestant faith that he had adopted as a young man to Roman Catholicism. Graunt had been brought up as a Puritan but had lived as an anti-Trinitarian for a number of years before his final conversion to Catholicism. Anti-Trinitarians rejected the notion that God is made up of three distinct beings, the Father, the Son, and the Holy Spirit.
Around the time that fire destroyed his fortune, Graunt became a manager at the New River Company, which was involved with furnishing London's water supply. Graunt's position there led to a rumor spread by enemies who despised his religious conversion. They accused Graunt of having played a role in starting the great fire of London, or at least of trying to interfere with water being transported to the city the night before the fire broke out. However, the accusation was disproved when an examination of the New River Company's books showed that Graunt had not become part of its management group until 21 days after the fire took place.
Lauded After Death
On April 18, 1674, after several years of working for the New River Company, Graunt died of jaundice, a disease of the liver. Among the mourners at his funeral were members of the London government and distinguished scientists, including Sir William Petty, who appeared grief-stricken at his friend's death. In addition to his famous book Observations, Graunt left behind another book titled Observations on the Advance of Excise, as well as a manuscript on religion.
In the centuries since his death, Graunt has been acknowledged by many historians and scientists for his important scientific contributions. In his 1741 work Divine Order in the Changes of the Human Race shown by its Birth, Death, and Propagation, German chaplain J. P. Sussmilch (1707-1767) praised Graunt as "a Columbus" for his discovery of the new field of demographics. In the opinion of Kenneth J. Rothman, writing in the British medical journal, The Lancet, "With [Graunt's book on the Bills of Mortality] he added more to human knowledge than most of us can reasonably aspire to in a full career."
Autobiography of Science, edited by Forest Ray Moulton and Justus J. Schifferes, Doubleday and Co., Inc., 1960.
Boorstin, Daniel J., The Discoverers: A History of Man's Search to Know His World and Himself, Random House, 1983.
Dictionary of Scientific Biography, edited by Charles Coulston Gillispie, Charles Scribner's Sons, 1972.
"John Graunt," Encyclopedia Britannica,http://www.britannica.com(December 14, 2000).
"John Graunt," http://es.rice.edu/ES/humsoc/Galileo/Catalog/FilesBAK1/graunt.html(December 14, 2000).
"Lessons from John Graunt," Lancet, January 6, 1996, http://www.findarticles.com(December 14, 2000). □
John Graunt (1620–1674) is generally regarded as having laid the foundations of demography as a science with the publication of his Natural and Political Observations Made Upon the Bills of Mortality (1662a). Graunt began, as many scien tists have done, by exercising idle curiosity—“Now having (I know not by what accident) engaged my thoughts upon the Bills of Mortality …” ([1662a] 1939, p. 3)—and proceeding to “observations, which I happened to make (for I designed them not) …” (ibid., p. 5). Characteristically, he did not believe that curiosity should remain idle: “finding some Truths, and not commonly-believed Opin ions … I proceeded further, to consider what ben efit the knowledge of the same would bring the World” (ibid., p. 18).
Graunt’s application of the statistical method to raw material had two essential elements: (1) clas sification of like with like, so as to break the data down into homogeneous groups, and (2) the comparison of those groups in order to recognize significant differentials. Another attribute of Graunt as a statistician was his ability to apply logic to his arithmetic. He never accepted a calculation if it offended his commonsense; nor did he accept it without a test, if he had the means of testing it.
As to classification, we may read in Chapter 2 of his Observations his very sound remarks about the identification of causes of death, then dependent on the observation of the “ancient matron” searchers (ibid., pp. 27-32). Deaths at advanced ages, he argued, can hardly be safely attributed to one specific cause, and not much worthwhile information can be expected about sudden deaths beyond their suddenness. As to comparison, we find in the same chapter his observation about the stability of proportionate mortality rates for certain causes, and in Chapter 4 (ibid., pp. 45-48) his observation that in plague years, deaths from causes other than plague were inflated to such an extent as to lead to his conclusion that of deaths from plague fully one-fifth were attributed to some other cause (in order to avoid the closure of the plague-infested dwelling and the virtual incarceration of the sur viving members of the household). Again in Chapter 3 (ibid., pp. 33-44), we may see how comparison of mortality rates for rickets with mortality rates referring to possible similar names for the same disease led Graunt, after examining the figures, to conclude that rickets was a new disease and not a new name for an old one. (This was probably a wrong conclusion, but Graunt was not a physician and would not have known that medical attention was at that time being drawn to the disease.)
The method of comparison was again employed when Graunt estimated the population of London in Chapter 11 (ibid., pp. 67-70). He used three methods and reconciled them. First, he estimated that a fertile woman had a baby every other year, that fertile women numbered half the married women, and that there were seven other members of a family (husband, 3 children, 3 servants); therefore, the population was 32 times the number of annual births. This gives 384,000. Next he estimated that in certain parishes there were annually three deaths from every 11 families; therefore, the number of deaths (13,000) multiplied by 11/3 yielded 48,000 families, or 384,000 persons. Finally, he observed 54 families per 100 square yards within the walls (12,000 families) and guessed that there were three times as many families outside the walls.
Graunt’s most important contribution to demography was his rudimentary life table. Its importance lies not in the table itself, which is indeed defective, but in the novelty of presenting mortality in terms of survivorship. Graunt began with only two observations—the proportion of births surviving to age 6 (.64) and the proportion surviving to age 76 (.01). He then assumed that a constant multiplier is involved in proceeding from the first proportion to the last by decennial intervals of age. He did not make clear how he got his multiplier (or “mean proportion,” as he called it), but it was obviously about .6. Michel Ptouka (1938) has put forward the hypothesis that the multiplier was (64 - 1)/100 = .63. D. V. Glass has suggested (1950) that Graunt made a second difference interpolation from ln=100, ln = 64, and l-n=l. The method and any error in it is not important. (Halley was not to make the correct calculation for another sixty years or so.) So much has been developed from this simple but immensely powerful thought that actuarial criticism would be quite out of place.
Graunt is rarely considered apart from another English scientist of the time, Sir William Petty. Both were of Hampshire stock; Graunt was born in 1620 and Petty in 1623. They became acquainted in or before 1650. It appears that their relationship was initially that of client and patron (Graunt being Petty’s patron; see Greenwood 1941-1943), but the roles were reversed after the fire of London in 1666.
Graunt was the son of a city tradesman and became a haberdasher and a man of substance. Petty, who had sampled the merchant navy, studied mathematics in France, spent a short time in the Royal Navy, returned to the Continent to study anatomy, spent some time in business in London, and went to Oxford in 1649, becoming a doctor of medicine by dispensation. Later he rose to be professor of anatomy and vice-principal of Brasenose. He became a candidate for a Gresham professor ship in London and made contact with Graunt. We do not know what interests they shared at that time or whether Graunt (or his father) had any influence in Petty’s subsequent appointment as Gresham professor of music. Soon after, Petty (who seems to have had no professional duties) went to Ireland and made a fortune. For many years Graunt remained a prosperous tradesman, but the fire of 1666 destroyed his business. A little later he became a Roman Catholic convert and was apparently not interested in rebuilding his business, for he was soon bankrupt. It was now Petty’s turn to be the patron, and Graunt, the client—and apparently not an easy one. Despite Petty’s at tempts to help him, Graunt’s financial troubles were with him until he died in 1674.
Petty’s vital statistical work was on a different level from that of Graunt. Petty had inspiration and brilliance, many ideas and a breadth of vision, but he did not pursue his ideas as persistently as Graunt did. It was Petty who proposed a central government statistical office and a system of census taking. He anticipated William Farr in estimating the economic loss due to mortality. Many of his calculations, however, do not stand up to the tests of consistency that Graunt would have applied. It seems to be generally agreed that Graunt made an immeasurably greater contribution to demography.
Essentially, Graunt was a man with an inquiring mind whose ideas laid the foundation of the political arithmetic that we now accept as part of good social organization and government. The Royal Society of London, of which Graunt was elected a fellow, commemorated the tercentenary of the publication of his Observations by holding a special series of scientific meetings to which leading demographers in England and other countries contributed papers (Glass 1963). The Institute of Actuaries of England paid its own tribute to Graunt by republishing, in a more modern format but without abridgment or alteration, his original Observations.
[For the historical context of Graunt’s work, seePublic Health; Vital Statistics; and the biography ofPetty. For discussion of the subsequent development of his ideas, seeLife Tables; Mortality; and the biographies ofKÖrÖsy; Lotka.]
(1662a) 1939 Natural and Political Observations Made Upon the Bills of Mortality. Edited with an introduction by Walter F. Willcox. Baltimore: Johns Hopkins Press. → See especially Chapter 2, “General Obser vations Upon the Casualties” Chapter 3, “Of Particu lar Casualties” Chapter 4, “On the Plague” Chapter 11, “Of the Number of Inhabitants.”
(1662b) 1964 Natural and Political Observations Mentioned in a Following Index, and Made Upon the Bills of Mortality: With Reference to the Government, Religion, Trade, Growth, Ayre, Diseases, and Several Changes of the Said City [London]. Journal of the Institute of Actuaries (London) 90:1–61. → Includes a three-page introduction by B. Benjamin.
Glass, D. V. 1950 Graunt’s Life Table. Journal of the Institute of Actuaries (London) 76:60–64.
Greenwood, Major (1941–1943) 1948 Medical Statistics From Graunt to Farr. Cambridge Univ. Press. → First published in Biometrika.
Newman, James R. 1956 Commentary on an Ingenious Army Captain and on a Generous and Many-sided Man. Volume 3, pages 1416-1419 in James R. Newman (editor), The World of Mathematics: A Small Library of the Literature of Mathematics From A’h-mose the Scribe to Albert Einstein. New York: Simon & Schuster.
Ptouka, Michel 1938 John Graunt, fondateur de la demographie: 1620–1674. Volume 2, pages 61-74 in International Congress for Studies on Population, Paris, 1937, Congreès international de la population. Paris: Hermann.
Sutherland, Ian 1963 John Graunt: A Tercentenary Tribute. Journal of the Royal Statistical Society Series A 126:537–556.
(b. London, England, 24 April 1620; d. London, 18 April 1674)
Graunt, apparently the eldest of seven or eight children born to Henry and Mary Graunt, received some formal “English learning” and, after he was sixteen, was apprenticed in his father’s profession of draper. He held various offices in the Freedom of the Draper’s Company and in the city government, and he prospered in his business. In February 1641 he married Mary Scott, who evidently bore him one son and three daughters. Graunt came to know prominent people in London, and before 1650 he had become a friend of William Petty.
After the publication of his only book in January 1662, Graunt was elected, at the request of Charles II, to membership in the Royal Society. He suffered serious losses from the great fire of 1666, and this crisis was worsened by legal harassments occurring after his conversion around that time to Catholicism (earlier he had converted from Puritanism to anti-Trinitarianism). In spite of assistance from Petty, Graunt remained in straitened circumstances until his death.
Graunt’s Natural and Political Observations … Upon the Bills of Mortality was the foundation of both statistics and demography. He had never formally studied mathematics, and the computations in his book were not more complex than what a successful businessman of that time could be expected to know. There has been much speculation over how much assistance Graunt received from Petty in writing the book. Undoubtedly Petty encouraged the undertaking and most likely made some contributions to it, but Graunt seems to deserve the lion’s share of credit. He got the idea for his investigation from “having (I know not by what accident) engaged my thoughts upon the Bills of Mortality,” which had been published for London since the end of the sixteenth century. These statistics were the primary basis for his study, although he supplemented them with parish christening records and data from a rural area, Romsey in Hampshire (Petty’s birthplace).
Since Graunt’s treatise was the staritng point for two sciences, both his discoveries and the form of his presentation were important. He began by listing the kinds of knowledge that could be gained from analyzing vital statistics. Next, he discussed with impressive sophistication the various kinds of defects in his data—geographical inconsistencies, irregular intervals between recordings, lack of thoroughness, inaccurate age approximations, and ambiguous disease nomenclature, and a bias against honest reporting of certain causes of death, such as syphilis. He published tables of some of the data and some important statistical regularities which he discovered were evident from inspecting the data: a few more boys were born than girls; women tended to live longer than men; the sex ratio was about equal and was stable; the numbers of people dying from most causes except epidemic diseases were about the same from year to year; the mortality rate was high among infants; the frequency of death was higher in urban than in rural areas.
Graunt carried his analysis further by deducing various characteristics of populations from his data. These ingenious attempts indicate a good understanding of the kinds of questions that are significant for demography. Usually he explained his steps in solving problems, but he seldom included the actual calculations; and sometimes he omitted important information. Furthermore, his indirect approach sometimes went beyond the reliable use of his data, and the accuracy of some of his answers was difficult to evaluate. His calculations of the populations of England and Wales and of London are two examples.
Since he did realize the shortcomings of his data, on several occasions Graunt set an excellent example by seeking verification of his estimates by different indirect methods. He introduced the use of statistical samples but did not pursue this subject far enough to determine the sizes of samples or means of selection needed for insuring accuracy. He gave information on infant and old-age mortality which modern demographers have shown contained an implicit life table, but Graunt’s method of computing it remains uncertain. He also realized that demographic procedures could be used to make projections concerning both past and future populations. In 1663 he furnished the Royal Society with a brief note on the rate of growth of salmon and the rate of increase of carp in a pond, which indicates that he also saw the value of studying animal populations.
I. Original Works. Graunt’s only book is Natural and Political Observations Mentioned in a Following Index, and Made Upon the Bills of Mortality (London, 1662; 2nd ed., 1662; 3rd ed., 1665; 4th ed., Oxford, 1665; 5th ed., London, 1676). This 5th ed. was reprinted in A Collection of the Yearly Bills of Mortality, From 1657 to 1758 Inclusive. Together With Several Other Bills of an Earlier Date…, presumably edited by Thomas Birch (London, 1759). There is a German trans. by Gottfried Schultz (Leipzig, 1702). There is also a reprint of the 5th ed. in The Economic Writings of Sir William Petty, Together With the Observations Upon the Bills of Mortality More Probably by Captain John Graunt, Charles Henry Hull, ed., 2 vols. (Cambridge, 1899; repr. New York, 1963), II, 319–431. Hull also gives a full bibliography of earlier eds. in II, 658–660, 641. There are two reprs. of the 1st ed.: Walter F. Willcox, ed. (Baltimore, 1939), and B. Benjamin, ed., in Journal of the Institute of Actuaries, 90 (1964), 1–61.
Graunt’s notes on fish were first published by Thomas Birch in The History of the Royal Society of London for Improving of Natural Knowledge, From Its First Rise, 4 vols. (London, 1756–1757), I, 267, 294. Hull quoted the notes from p. 294 following his repr. of Graunt’s book, II, 432.
II. Secondary Literature. The most important contemporary accounts of Graunt are by John Aubrey and Anthony à Wood: Aubrey’s Brief Lives, Oliver Lawson Dick, ed. (Ann Arbor, Mich., 1957), pp. 114–115; and Anthony à Wood, Athenae Oxonienses, 2nd ed., 2 vols. (London, 1721), I, col. 311. Wood’s account has been quoted in full in James Bonar, Theories of Population From Raleigh to Arthur Young (London, 1931; facs. repr., 1966), pp. 69–71. There are two modern investigations of his life: C. H. Hull, in Economic Writings of ... Petty, I, xxxiv-xxxviii; and D. V. Glass, “John Graunt and His Natural and Political Observations,” in Notes and Records. Royal Society of London, 19 (1964), 63–100, see 63–68, notes on 89–94.
The question of Petty’s contribution to Graunt’s book has been discussed in Glass, op. cit., pp. 78–89, notes on pp. 97–199; Hull, op. cit., I, xxxix-liv; Major Greenwood, Medical Statistics From Graunt to Farr (Cambridge, 1948), pp. 36–39; Walter F. Willcox, introduction to Graunt’s Natural and Political Observations (Baltimore, 1939), pp. iii-xiii; and P. D. Groenewegen, “Authorship of the Natural and Political Observations Upon the Bills of Mortality,” in Journal of the History of Ideas, 28 (1967), 601–602.
Graunt’s contributions to statistics and demography are surveyed and evaluated in B. Benjamin, “John Graunt,” in International Encyclopedia of the Social Sciences, VI (1968), 253–255; Glass, op. cit., pp. 69–78, notes on pp. 95–97; Hull, op. cit., I, lxxv-lxxix; Greenwood, op. cit., pp. 30–35; Harald Westergaard, Contributions to the History of Statistics (London, 1932), pp. 16–23; Ian Sutherland, “John Graunt: a Tercentenary Tribute,” in Journal of the Royal Statistical Society, 126A (1963), 537–556; and A. Wolf, F. Dannemann, A. Armitage, and Douglas McKie, A History of Science, Technology and Philosophy in the 16th & 17th Centuries, 2nd ed. (New York, 1950), pp. 588–598.
On the background situation for much of the bills of mortality used by Graunt, see Charles F. Mullett, The Bubonic Plague and England. An Essay in the History of Preventive Medicine (Lexington, Ky., 1956). Also relevant, and still useful, is the discussion by William Ogle, “An Inquiry Into the Trustworthiness of the Old Bills of Mortality,” in Journal of the Royal Statistical Society, 55 (1892), 437–460. Norman G. Brett-James has written a very useful paper on the collection of the London data; “The London Bills of Mortality in the 17th Century,” in Transactions of the London & Middlesex Archaeological Society, 6 (1933). 284–309.
The early reception of Graunt’s book is discussed in Robert Kargon, “John Graunt, Francis Bacon, and the Royal Society: the Reception of Statistics,” in Journal of the History of Medicine and Allied Sciences, 18 (1963). 337–348.
Frank N. Egerton, III
Graunt, John 1620-1674
John Graunt is recognized as the father of demography for his systematic yet critical use of population data to investigate demographic processes. He originated a number of demographic techniques and demonstrated a healthy skepticism of his own data.
Graunt was born in England in 1620. He was the son of a draper and, after completing his apprenticeship, he inherited his father’s business. Graunt acquired some degree of wealth and prestige and rose through the ranks of civil service, although he was not among the educated class of his day.
As a pastime, Graunt studied the Bills of Mortality— birth and death registers published weekly and annually in the London Times throughout the seventeenth century. Birth data was collected from christenings; mortality data was collected by older women, called searchers, who were paid to inquire about cause of death from family and physicians. Graunt’s Natural and Political Observations on the Bills of Mortality, which appeared around 1662, explored many demographic questions. His empirical investigation revealed that females tended to have a longer lifespan than males, that London was growing through internal migration from the country, and that the population of London was actually much smaller (around 460,000 people) than commonly asserted (estimates ranged up to seven million).
Graunt also formulated a number of methods that continue to be used by demographers today. He expressed the number of male births relative to female births as a ratio, creating what has come to be known as the sex ratio at birth. He estimated a doubling time for the growth of the city of London. In addition, Graunt observed that mortality varies by age. This insight led him to develop the first life table —a table that follows a virtual population of one hundred people through the age-specific mortality rates of the actual population. Edmund Halley (1656–1742) later perfected the life table and gave it its actuarial application.
One of Graunt’s most important methodological contributions was a skepticism of his own data. Graunt was concerned with unavailable data, poorly defined categories, misspecification of the cause of death, and under-reporting. He discussed at length the possibility of searchers being inaccurate, bribed, or drunk at the time of inquiry.
Graunt’s work also made the critical contribution of substantive interpretation. Previously, the Royal Statistical Society’s official goal was merely to gather data, not to interpret it. The Society claimed that “threshing out” the implications of data should be left to the court (i.e., politicians), a position that protected the Society from appearing partisan, but discouraged demographic research.
Late in life, Graunt converted to Catholicism. In the politically and religiously charged atmosphere of England at the time, his conversion had tragic consequences. He was forced to resign from his positions in civil service. The Great Fire of London in 1666 destroyed his home—a setback from which he never recovered. He lived out his last years with the financial help of his friend William Petty (1623–1687). Graunt died in 1674 in such poverty that the Draper Society awarded his widow £4 annually for her upkeep.
Sutherland, Ian. 1963. John Graunt: A Tercentenary Tribute. Journal of the Royal Statistical Society 126 (4): 537–556.
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.
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.
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.
Like many of his literate and well-educated contemporaries, John Graunt (1620–1674), a London merchant and haberdasher, was an amateur scientist. He was a member of the small community of scholars who were early Fellows of the Royal Society, which was founded by King Charles II just as Graunt reached his years of greatest creativity. Graunt was interested in the fluctuations in epidemics, especially the plague, and how these caused the numbers of deaths, and the age at death, to vary from one year to another. For over one hundred years English parishes had kept records of baptisms and deaths, and what was then under-stood about causes of death was derived from these "bills of mortality," which Graunt collected and analyzed. He found differences in death rates between the sexes, between the city and the outlying rural and more remote regions, and he analyzed the ebb and flow of the epidemics of plague. He published his work in Natural and Political Observations … Made upon the Bills of Mortality (1662), now regarded as a seminal work in vital statistics.
Graunt influenced, and was influenced by, Sir William Petty (1623–1687), author of Political Arithmetic and other works that analyzed available facts in a number of areas, including life expectancy and earning capacity, emphasizing their economic and fiscal implications. There has long been debate about which of these two men should be credited with founding the statistical study of births and deaths. Both deserve to be remembered, but of the two, John Graunt, though he had less formal education, was probably the more creative and innovative. His writings were clear and concise, a model of what the analysis of vital statistics should be. Graunt therefore can justly be described as the founder of vital statistics.
John M. Last
(see also: Bills of Mortality; Mortality Rates; Vital Statistics )
English statistician generally credited as the founder of scientific demography. A founding member of the Royal Society, Graunt began studying London death records dating back to 1532. He noticed a number of patterns, which he discussed in Natural and Political Observations... made upon the Bills of Mortality (1662), classifying death rates according to cause, and identifying overpopulated conditions as a mortality-increasing factor. He also developed one of the earliest life-expectancy charts, which was based on his studies of survivorship. Graunt's ideas had a profound effect on the demographic efforts of Sir William Petty (1623-1687), and on the mathematical studies of Sir Edmund Halley (1656-1742).