To check the reaction towards the old religion he wrote several works of great power, especially his Theologiae Jesuitarum praecipua capita (1562), an incisive attack on the principles of the society, and the Examen concilii Tridentini (four parts, 1565-66-72-73), his greatest work.
In 1810 the examen pro facultate docendi first made the profession of a schoolmaster independent of that of a minister of religion.
Dubois's Examen de la geographie de Strabon (Paris, 1891) should also be consulted.
His great reputation and his diplomatic experience gave a special weight to the attacks which he published on the policy of the continental allies, two of his works attracting special attention, Du Congres de Troppau ou Examen des pretentions des monarchies absolues a l'egard de la monarchie constitutionelle de Naples (Paris, 1821), and Les Cabinets et les peuples depuis 1815 jusqu'd la fin de 1822 (Paris, 1822).
Soon after this he published his first work, Examen de livre de la reunion du Christianisme (1671).