Born Saint-Malo, 1782; died Paris, France, 1854. Converted from a careless life, he began ecclesiastical studies and was ordained 1817. His "Essai" (essay) on religious indifference caused him to be hailed as the foremost champion of the Church, but his second volume contained a philosophical system opposed by many churchmen. With Lacordaire, Maurice de Guerin and others, he founded the Congregation of Saint Peter, a religious society for the defense of the Church. After the Revolution he established the journal, "L'Avenir," to defend the Church against the government of the House of Orleans, and to oppose Gallicanism. The Encyclical "Mirari vos" of Gregory XVI condemned his ideas, and he discontinued the journal, but refused to submit to the Encyclical, renouncing his ecclesiastical functions, 1833, and publicly declaring his rupture with the Church by publishing (1834) "Paroles d'un croyant" (Sentiments of a believer), a denunciation of kings and priests. In 1848 he was elected deputy to the Constituent and Legislative Assemblies, but the coup d'etat of 1851 ended his political career. He died unreconciled to the Church.