Louis Claude Saint-Martin, marquis de, a French metaphysician, born in Amboise, Jan. 18, 1743, died near Paris, Oct. 13, 1803. For a while he practised as an advocate at Tours, but in 1765 was a lieutenant in a regiment in garrison at Bordeaux, where he became interested in mystical speculations, and subsequently studied the works of Jakob Boehm and Swe-denborg. In 1771 he left the army and went to Lyons, where he published his first book, Des erreurs et de la vérité, par un philosophe inconnu (1775), a refutation of the theories of materialism. He spent some years in Paris, visited England in 1786 and Italy in 1787, and after his return resided in Strasburg till 1791, then in Amboise till 1795, when he returned to Paris. His principal works are: Tableau na-turel des rapports qui existent entre Dieu, l'hom-me et l'univers (Lyons, 1782), showing that we must explain things by man and not man by things; L'Homme de désir (1790); Ecce Homo (1792); De l'esprit des chosen (1800); and Le ministère de l'homme-esprit (1802). - See his Correspondance with Kirchberger (Paris, 1862), and Saint-Martin, le philosophe inconnu, by Matter (1862).