Le jésuite namurois Antoine Thomas (1644-1709) compose la Synopsis Mathematica durant son enseignement de mathématiques à l’université de Coimbra au Portugal (1678-1680). Fruit de ses lectures et de son enseignement, son livre est une sorte de manuel didactique destiné aux futurs missionnaires de la mission de Chine. Le but n’est pas de former des mathématiciens, ni des astronomes de métier, mais de fournir de bonnes connaissances et de permettre aux missionnaires d’exécuter quelques travaux scientifiques.

L’ensemble des 2 tomes comprend plus de 1000 pages et se déploie en 15 traités. Thomas y traite de presque toutes les disciplines mathématiques, passant de l’arithmétique, de la géométrie élémentaire et pratique aux cadrans solaires, à la trigonométrie sphérique, aux astrolabes, au calendrier et finalement à l’astronomie. Celle-ci constitue le dernier recueil, le plus conséquent, le meilleur et la finalité de l’œuvre. Les 14 autres sont conçus comme des étapes préliminaires aboutissant vers ce dernier traité, considéré comme le plus important pour la mission de Chine. C’est ainsi que, notamment, l’auteur y développe de manière claire et accessible comment calculer les éclipses du Soleil et de la Lune. Non une démonstration, mais des règles d’emploi et des exemples en vue d’aider des religieux « profanes » dans des calculs et des observations astronomiques. Thomas achève son livre par un complément comprenant 38 tables numériques calculées au méridien de Coimbra.

The author (1644-1709), descendant of a notable family of Namur and pupil of the Jesuit schools of the "Provincia Gallo-Belgica", was – in the general enthusiasm for the "Indian" mission, especially Japan and China – since an early phase of his Jesuit career preparing himself to the Japanese mission, which included – according to contemporary expectations – a more than average experience of (theoretical and practical) mathematics. This he tried to acquire during his formation years, and his period as a teacher in the "Collège de Marchiennes" in Douai, in 1671-1675. When finally having been authorized to go to the Far East (1677), he decided to compose a "mathematical primary" for the future generations of novices of the China mission ("Indipetae"), selecting those aspects which had more importance in China (Japan), and leaving more detailed questions outside the discussion. As such, there was the model of Mario Bettini’s Apiaria and Aerarium (Bologna, 1642 and 1648), both written for Italian Jesuits in China, who had to work without disposing of a rich library of up-to-date Western books on mathematics; in its didactical conception, however, it was a novelty.

When in the immediate preparation of his departure for China he was teaching for two years (1678-1680) mathematics at the Colégio das Artes in Coimbra – with a public of Portuguese Jesuit novices, among them some candidates for the China (-Japan) mission – he periodically worked on this compendium, describing the most important of the "mixed mathematics" (such as geometry, geography, hydrography, music; in vol. II: optics, statics, sundials, trigonometry; calendar; astronomy). He relied mainly on books circulating in France and NW. Europe, using De Chales’s recently published Cursus seu Mundus Mathematicus (Paris, 1674) as a general reference work to which the readers were referred for furthering and deepening their knowledge. At the same time, references to the Coimbra context prove the work was written, or at least completely revised and updated during his stay in Coimbra. Although it was also planned to be printed there, this did not succeed; the manuscript was sent to Douai, where it was printed – with a subvention of Maria de Guadalupe, Duchess of Aveiro and one of the main supporters of Jesuit missions in the last quarter of the 17^th century – in 1685, by Michel Mairesse. The first copy in China arrived before 1688, where it got a limited reception, especially in Thomas’s own teaching. The schematic and rather poor illustrations – far from the "ornatus" Thomas had expected – made the volume less well appropriate to be "offered" to the Chinese Emperor. Yet two copies from the former pre-1773 Jesuit collections in China still survive, both with an interesting "biography". An analysis of the mathematical contents (H. Bosmans) shows that the expected level of the readers was rather low (elementary geometry; fundamentals of arithmetics and proportions): because of this, the whole text is written in a common Latin, with the omission of all demonstrations; that astronomy is by far the best part certainly reflects the central point astronomy had in Jesuit mathematical activities in China.

Despite its intention of being a low profile "practical" introduction on behalf of future "Indipetae", intensive investigations could only trace some 30 copies spread over the world (see my forthcoming "census"). This suggests that neither in Europe the work had received that broad reception, probably for its too "basic" character (and the omission of "algebra"). In 1729 the unsold stock was published again, with a new title page, by C. L. Derbaix, former commercial partner of the Veuve Mairesse.  Only two copies of this 2^nd "edition" – in fact the recycled 1^st ed. – are known. Still, in 1756 Inacio Monteiro (Compendio dos elementos de Matematica, Coimbra, 1754-1756) refers to A. Thomas’s Synopsis as one of the three main sources for whom wanted to acquire the "necessary principles of physics".

The copy in Namur is of the 1^st edition, and consists only of the 1^st part. It stems from the library of the former "Collège philosophique" of the Belgian Jesuits in Heverlee (Leuven), destroyed in 1940.  It has a double inscription: "Ce livre est à M[onseigneu]r de Baillencourt Anno 1697 […] Anno 1698"; "L. S [?] S. [?] de Baillencourt", with reference to a first owner, who cannot be identified with certainty, although he is known from some other mathematical books (in 1693 he signed a copy of Ozanam).

Noël Golvers
Katholieke Universiteit Leuven - F. Verbiest Instituut
May 2013

Bibliography

- Mme Yves de Thomaz de Bossierre, Un belge mandarin à la Cour de Chine aux XVIIe et XVIIIe siècles. Antoine Thomas, 1644-1709 Ngan to P'ing-Che (La Chine au temps des Lumières, n°3), Paris, 1977.

- H. Bosmans, L’oeuvre scientifique d’Antoine Thomas de Namur, S.J. (1644 - 1709), dans Annales de la Société scientifique de Bruxelles, t. 44, 1924-1925, p. 169-208; t. 46, 1926, p. 154-181.

- C. Matagne, Répertoire des ouvrages du XVIIe siècle de la Bibliothèque du CDRR (1651-1700). IIe partie: M – Z. Index, Namur, 1992, p. 745, T155.

- N. Golvers, Jesuit Sinipetae and their mathematical textbooks: Antoine Thomas and his Synopsis Mathematica (Douai, 1685) [forthcoming].