Morin, Jean-Baptiste

MORIN, JEAN-BAPTISTE

(b. Villefranche, Beaujolais, France, 23 February 1583; d. Paris, France, 6 November 1656)

medicine, astronomy, astrology.

Morin was a strange person but typical of his age in that he undertook very varied activities. He was sufficiently successful and intelligent to acquire a reputation in his own time, but he failed to demand of himself the thorough discipline that would have enabled him to produce truly scientific work. A medical doctor at first, he then took an interest in all the topics associated with hermetic literature. In order to penetrate the mysteries of nature he studied mining and astrology (he was later to draw up an astrological chart for the infant Louis XIV). His talents won him the support of influential people, and in 1630 he was professor of mathematics at the Collège Royal (now Collège de France), a position he held until his death.

A polemicist by disposition, he quickly sought to distinguish himself in the major debates most likely to bring him widest attention. In 1624 he published a defense of Aristotle in conjunction with the refutation of the theses of Antoine de Villon and of étienne de Claves, both of which had been condemned by the Sorbonne. He opposed Galileo before and after the trial of 1633. He attacked Descartes in 1638, flattering himself that he had detected how bad his philosophy was from the moment that they had met, before Descartes’s departure for Holland.

If Morin suffered injustice in the judgments reached by his contemporaries, especially Boulliau, he owed his poor reputation to the way in which he conducted his disputes. This fault is best illustrated in the matter of the determination of longitudes. During the very period when he was presenting himself as the champion of the immobility of the earth, Morin simultaneously wished to prove that he was capable of drawing inspiration from Kepler, of correcting the Rudolphine Tables, and of proposing a method for finding longitudes that would always be usable at sea and sufficiently precise for navigation. The only original thing about this method, which was based on the observation of the moon, was its claim of utilizing the movements of the moon relative to the stars as a universal clock and of generalizing this phenomenon to calculate the difference in hours between two positions on the earth. The method required new observational instruments, which could be used with sufficient precision on ships, the improvement of the mathematical solution of spherical triangles, and the possibility of a systematic checking of tables of lunar motion established for a given position. Morin glimpsed these three facets of the problem and made an important contribution to instrumental technique by utilizing telescopes for the sights and verniers for the measurement of angles; but he was incapable of mastering the complex problem of precision in a process involving both observation and computation. Ambition and the desire to obtain a pension from Richelieu made him deaf to all objections.

From 1626 to 1628 Morin undertook research in optics with the engineer Ferrier, in whom Descartes had placed his hopes. Shortly afterward his friendships with Peiresc and Gassendi helped him in observational astronomy. But the affair of the longitudes, with the prolonged debate (1634-1639) that put him in opposition to Étienne Pascal, Mydorge, and Beaugrand, alienated the scientific community, and he continued his work largely in isolation.

Morin’s posthumously published Astrologia gallica reveals that he had interesting ideas concerning the theory of heat and the temperature of mixtures. Moreover, in the correspondence of Mersenne and Descartes references to Morin are not entirely negative. Despite his undoubted talents, Morin’s philosophical and scientific choices were too often political ones and prevented him from producing the caliber of work of wihch we now see he was capable.

BIBLIOGRAPHY

I. Original Works. For works of Morin see Astronomicarum domorum cabala detecta (Paris, 1623); Refutation des thèses … d’A. Villon et E. de Claves … contre les doctrines d’ Aristote (Paris, 1624); Famosi et antiqui problematis de telluris motu vel quiete hactenus optata solutio (Paris, 1631); Trigonometriae canonicae libri tres quibus planorum et sphaericorum triangulorum theoria … adjungitur liber quartus pro calculi tabulis logarithmorum (Paris, 1633); Pro telluris quiete (Paris, 1634); Astronomia jam a fundamentis integre et exacte restituta … (Paris, 1640); La science des longitudes … (Paris, 1647); and Astrologia gallica … (The Hague, 1661), published posthumously under the auspices of Marie Louise of Gonzaga, queen of Poland, which also contains a Latin trans. of the anonymous Vie de Morin (1660), the French original of which is lost.

II. Secondary Literature. For information about Morin see P. Bayle, Dictionnaire historique et critique, II, pt.1 (Rotterdam, 1697), 602–612; M. Delambre, Histoire de l’astronomie moderne, (Paris, 1821), 236–273; G. de Fouchy, “Sur la date de l’application des lunettes aux instruments d’observation …,” in Mèmoires de l’Académie royale des sciences pour l’année 1783 (1787), 385–392; L. Moreri, Le grand dictionnaire historique, VII (Paris, 1759), 786–788; and J. Montucla, Histoire des mathématiques (Paris, 1799), II, 336–1802; IV, 543–545.

Pierre Costabel