Roberval, Gilles Personne de

1. Dates

Born: near Senlis, 10 August 1602

Died: Paris, 27 October 1675

Dateinfo: Dates Certain

Lifespan: 73

2. Father

Occupation: Peasant/Small Farmer

He came from a family of simple farmers.

Although nothing explicit is said, the phrase "simple farmers" says to me that they were poor. What he himself said about his education certainly says the same thing.

3. Nationality

Birth: French

Career: French

Death: French

4. Education

Schooling: No University

Roberval writes that he was born and educated among the people (inter multos). He left his family at an unknown age. He embraced the study of mathematics at the age of fourteen. He travelled to various regions of the country earning a living from private lessons. He continued to educate himself by attending classes at the universities in the regions he visited. In Bordeaux where he met Fermat and took on François du Verdus as a pupil he may have attended the university.

5. Religion

Affiliation: Catholic

He is buried in the church of St. Severin. Auger writes that according to Lebeuf Roberval is buried in the choir, but Auger was unable to locate any signs.

6. Scientific Disciplines

Primary: Mathematics, Mechanics, Physics

Subordinate: Natural Philosophy

Roberval was a leading proponent of the geometry of infinitesimals which he claimed originated with Archimedes. (He was unfamiliar with the work of Cavalieri.) He wrote on finding areas, a book titled Traité des indivisibles, which appeared in a collection of Académie works. In addition to his work on areas he wrote treatises on algebra and analytic geometry. His method of the "composition of movements" makes him the founder of kinematic geometry of which the most famous application was the construction of tangents.

Many of Roberval's writings were published in collections of other works by members of the Académie (1693). Since few of his works appeared in the period that followed, Roberval was eclipsed by Fermat, Pascal, and his adversary Descartes. Only two works were published separately, Traité de méchanique (1636) and Aristarchi Samii de mundi systemate (1644).

From 1644-8 he played an important role in the relations with Italy involving the barometric experiments.

At the same time (1647) he entered into another polemic with Descartes on the center of oscillation of the compound pendulum.

He advocated the joining of experiment to reason and wrote a philosophical work that showed evidence of his positivism.

7. Means of Support

Primary: Schoolmastering, Academia, Government

At an unknown date he left home and travelled through various regions of the ocuntry earning a living by giving private lessons.

In 1628 he arrived in Paris and made contact with the Mersenne circle: Claude Mydorge, Claude Hardy, and Etienne and Blaise Pascal.

He was appointed professor of philosophy at the Collège de Maitre Gervais in 1632. Costabel writes that Roberval had the postion of "boursier" de mathematiques au Collège de Maitre Gervais. This position, which he held until his death, involved private tutoring at the Collège for a salary and lodging.

In 1634, he won the triennial competition for the Ramus chair at the Collège Royal. He kept this post for the rest of his life. Many attribute the secrecy of his findings to his desire to keep the Ramus chair, for reappointment to which he had continually to compete.

By 1655 he added another academic post to his career, Gassendi's chair in mathematics at the Collège Royal.

He was a founding member of the Académie and remained a member until his death.

8. Patronage

Types: Aristrocrat, Scientist, Unknown

I consider his tutoring of François du Verdus to be an aspect of patronage.

Mersennne published some of Roberval's works in his own treatises.

Someone had to have been behind the appointment to the Académie.

9. Technological Involvement

Types: Instruments, Cartography

In 1699, he presented to the Académie plans for a particular type of balance that bears his name.

He suggested the application of telescopic sights to the quadrant and sextant.

On the problem of the vacuum he wrote two Narrationes. In the second one he described a very ingenious apparatus that he had invented to support his theory. This device served as a prototype for the one in Pascal's experiment on "the vacuum in the vacuum."

In the Académie he participated with Picard in the work on cartography. He composed a mémoire on the method of mapping France.

10. Scientific Societies

Membership: Académie Royal des Sciences 1666-75

Roberval was a charter member of the Académie.

When he arrived in Paris in 1628 he immediately became acquainted with the members of the Mersenne circle. Mersenne especially held him in high esteem.

Sources

1. Condorcet, Eloges des académiciens de l'Académie Royale des Sciences, (Paris, 1773). Q171.C746 1968 Leon Auger, Un Savant Meconnu: G.P. de Roberval, (Paris, 1962).
2. QA29.R56.A92
3. Robert McKeon, "Les débuts de l'astronomie de precision," Physis, 13 (1971), 225-88; 14 (1972), 221-42; especially 14, 231.
4. "Roberval" in Pierre Costabel and Monette Martine, Quelques savants et amateurs de science au XVIIe siècle, (Paris, 1986), pp. 21-31. Z7404.C78 1986 Guy Picolet, ed., Jean Picard et les débuts de l'astronome de precision au XVIIe siècle. Actes du colloque du tricentaire, (Paris, 1987), pp. 209, 249-52.

Compiled by:

Richard S. Westfall

Department of History and Philosophy of Science

Indiana University

Note: the creators of the Galileo Project and this catalogue cannot answer email on geneological questions.