Louis Claude de Saint-Martin

Louis Claude de Saint-Martin (18 January 1743 – 14 October 1803) was a French freemason and philosopher, known as le philosophe inconnu ("the unknown philosopher"), the name under which his works were published. He was an influential Christian mystic whose legacy, together with that of his mentor Martinez de Pasqually, inspired the founding of the Martinist Order. Initiated under the name "Eques a Leone Sidero", he was a member of the Societé des Initiés, an inner order of mystical freemasons directed by Jean-Baptiste Willermoz, in which they have allegedly received revelations from an "Unknown Agent" (Agent Inconnu).

Léonce de Saint-Martin, composer and organist, was a distant relative of Louis-Claude de Saint-Martin.