LESEUR, THOMAS. – Theologian, philosopher, and mathematician of the Order of Minims, b. at Rethel (Champagne) in 1703, d. in Rome on 22 September 1770. After teaching theology and philosophy in his province, he was sent (1734) to Rome, where, JACQUIER, FRANÇOIS (v.), he carried out his lengthy scientific activity.
In addition to the works written in collaboration with Jacquier, he wrote Mémoire sur le calcul intégral (Rome 1748); his theological works, together with other manuscripts, perished in the Napoleonic dispersal of the Roman convent of Trinità.
BIBL.: A. Condorcet O'Connor, Oeuvres complètes de C. Condorcet, II, Paris 1847, Eloge de p. L. S., pp. 130–37; Acta capitolorum generalium Ord. Minimi, II, Rome 1916, pp. 190, 199, 475; G. Roberti, Disegno storico dell'Ord. dei Minimi, III, there 1922, pp. 807–11; F. Bonnard, Histoire du Couvent de la Trinité du Mont Pincio à Rome, Rome-Paris 1933, pp. 50, 178–85. Gennaro Moretti