Hommage à Roland Pressat

Roland Pressat, a math teacher who became a senior researcher at INED, was instrumental in teaching and diffusing demographic analysis methods.

Born in 1923, Pressat began his career as a mathematics teacher in the French public education system, but at the age of 30 he changed paths, entering INED to do demography research. “With nothing more than an undergraduate degree in mathematics, he wrote to Alfred Sauvy [who had founded the Institute in 1945] to ask how he might become a demographer,” wrote Gérard Calot, INED director from 1972 to 1992, in his preface to the festschrift published by Population upon Pressat’s retirement. The ease with which Pressat joined the Institute seemed astounding today. And he spent almost his entire career at INED—38 years.

When Pressat arrived, formal training in demography was virtually non-existent; researchers learned as they went along. But when Alfred Sauvy invited Pressat for an interview after receiving his letter, the younger man managed to convince him to offer him a position at INED. A more than felicitous decision. In conducting his first research studies—focused primarily on the demographic situation of France—under the guidance of Louis Henry, Pressat “learned” demography remarkably fast and was soon tapped to write a textbook. He assumed that task with energy and passion, honing his first drafts in his first courses at the Institut de Démographie de Paris (IDUP). In 1961 he published the first edition of what would become a fundamental reference work in the discipline: Analyse démographique. Méthodes, résultats, applications. The book was republished in 1969.

It enjoyed immense success in Europe and was soon translated into Russian, Polish, and Spanish. And Pressat did not stop there, leaving us an abundant collection of works, including Principes d’analyse (1966), Pratique de la démographie (1967), Démographie sociale (1971), Démographie statistique (1972), Les méthodes en démographie (1981), and of course his Dictionnaire de démographie (1979), translated into a number of European languages, including English but also Chinese and Vietnamese (complete bibliography link below). He was rigorous not only in his use of figures or equation chains, but also in achieving verbal clarity and quality. In all his writings, in every sentence, he found precisely the right words to express his thinking.

Roland Pressat did not revolutionize demography training, he created it. A teacher through and through, he managed to convince cohorts of students from all horizons that demography was essential to understanding a wide range of social phenomena, together with the right tools for analyzing them. For over 50 years, no demographer’s office or book shelf has gone without the “Pressat.” His method of demographic analysis is based on “pure” statistical measurement of phenomena (fertility, mortality, etc., an example being the probability of getting married), free of interference from “disrupting” factors, and on a rigorous distinction between “cohort” analysis and analysis “of the moment”—the renowned  “longitudinal” and “cross-sectional” perspectives.

Pressat did not invent the theory of population dynamics, which was the work of Alfred Lotka (1880-1949) or write a treatise on demography, as did Adolphe Landry (1874-1956) or work to establish a general theory of population, an achievement of Alfred Sauvy (1898-1990); nor did he construct population models meant to represent all possibilities, in the manner of Jean Bourgeois-Pichat (1912-1990), Ansley Coale (1917-2002), or Paul Demeny. In the festschrift published upon his retirement, Massimo Livi Baci brilliantly positioned Pressat’s particular contribution to the empirical school of demographic science: ever-appropriate methodological principles that were complementary to the formally abstract approaches being developed in English-language demography. Pressat’s work made it possible to “set up a precise frame of reference, without which the most advanced research studies would have lost some of their meaning and utility” (article link below).

With unrivalled rigor and a set of well-mastered statistical tools that he constantly worked to pare down, Pressat built instruments for measuring the key factors of population trends and considerably, consistently enriched the connections between the concepts and indices necessary for accurate understanding of those phenomena. Identifying all the subtleties and pitfalls of demographic statistics, Pressat made the work of estimating synthetic indicators—indicators that are essential for analyzing the combined effects of demographic flow factors on population structure and structure trends—both understandable and accessible. Together with Louis Henry and Paul Vincent, he founded what is called the French (and by extension, the French-language) school of demography, which, after persuading demographers in Europe of its accuracy and relevance, finally reached the other side of the Atlantic.

The Canadians knew what they were doing when they offered Pressat a full professorship in the University of Montreal’s demography department, where he was a great success. After some years there, however, Pressat requested to return to INED. The problem at the time was that INED researchers did not have permanent civil servant status, and in leaving France for Montreal Pressat had had to resign from his position at the Institute; to return, he had to be hired a second time. But this was a mere formality, and he was soon able to rejoin the Institute he knew and valued so highly and that valued him in return.

Alongside his passion for teaching, Roland Pressat produced many demography papers and research studies. For nearly twenty years he was the self-effacing anonymous author of the Rapport au Parlement sur la situation démographique de la France, which INED was called upon to produce every year as part of the official missions on which it was founded in 1945. This activity led him to create a special section in INED’s journal Population called the “Conjoncture démographique,” a regular presentation and analysis of the demographic situation in the country at given moments in time.

“Displaying admirable eclecticism,” wrote Gérard Calot, Pressat was as comfortable making demographic projections as he was analyzing fertility, contraception and abortion, nuptiality, divorce rates, mortality, and population aging, and investigating such diverse regions as his native France and China, the Soviet Union, and developing countries. He also showed continual interest in France’s medical profession, as attested by his regular contributions to Le Concours medical from 1956 to 1991.

Lastly, Roland Pressat was not only an impassioned demographer, but also an art lover and collector.

Jacques Vallin, Patrick Festy, Xavier Thierry

Online: January 2020