He came from a rich family which, according to family tradition, had been converted from Judaism to the Catholic faith by Saint Desiderius of Vienne in 607. From the same family sprang the better known Frédéric Ozanam. Though he began the study of theology to please his father, he was more strongly attracted to mathematics, which he mastered without the aid of a teacher. At the age of fifteen he produced a mathematical treatise. Upon the death of his father, he gave up theology after four years of study and began, to give free private instruction in mathematics at Lyon. Later, as the family property passed entirely to his elder brother, he was reluctantly driven to accept fees for his lessons.
In 1670, he published trigonometric and logarithmic tables more accurate than the existing ones of Ulacq, Pitiscus, and Briggs. An act of kindness in lending money to two strangers brought him to the attention of M. d'Aguesseau, father of the chancellor, and he secured an invitation to settle in Paris. There he enjoyed prosperity and contentment for many years. He married, had a large family, and derived an ample income from teaching mathematics to private pupils, chiefly foreigners.
His mathematical publications were numerous and well received. Récréations (published 1694) was later translated into English and is well known today. He was elected a member of the Académie des Sciences in 1701. The death of his wife plunged him into deep sorrow, and the loss of his foreign pupils through the War of the Spanish Succession reduced him to poverty. He died in Paris on April 3, 1718 (frequently cited as 1717 because of an error in "éloge de Fontenelle").
Ozanam was honoured more abroad than at home. He was devout, charitable, courageous, and of simple faith. As a young man he had overcome a passion for gambling. He was wont to say that it was for the doctors of the Sorbonne to dispute, for the pope to decide, and for a mathematician to go to heaven in a perpendicular line.
- Table des sinus, tangentes, et sécantes (1670)
- Methode générale pour tracer des cadrans (1673)
- Geometrie pratique (1684)
- Traité des lignes du premier genre (1687)
- De l'usage du compas (1688)
- Dictionnaire mathématique (1691)
- Cours de mathématiques (Paris, 1693, 5 vols, tr. into English, London, 1712)
- Traité de la fortification" (Paris, 1694)
- Récréations mathématiques et physiques (1694, 2 vols, revised by Montucla in 1778, 4 vols)
- Nouvelle Trigonométrie (1698)
- Méthode facile pour arpenter (1699)
- Nouveaux Éléments d'Algèbre (1702)
- La Géographie et Cosmographie (1711)
- La Perspective (1711).
Ozanam, Jacques, (1844). Science and Natural Philosophy: Dr. Hutton’s Translation of Montucla’s edition of Ozanam, revised by Edward Riddle, Thomas Tegg, London. Read online- Cornell University
- O'Connor, John J.; Robertson, Edmund F., "Jacques Ozanam", MacTutor History of Mathematics archive, University of St Andrews.