The Search for Truth by Natural Light

The Search for Truth by Natural Light (La recherche de la vérité par la lumière naturelle) is an unfinished philosophical dialogue by René Descartes “set in the courtly culture of the ‘honnête homme’ and ‘curiosité’.” It was written in French (presumably after the Meditations was completed) but that was lost around 1700 and remained lost until a partial copy was discovered in G.W. Leibniz's papers in Hanover in 1908 and published in the Adam-Tannery edition of Descartes's works and correspondence (vol. X, pp. 495-532). A Latin translation, Inquisitio Veritatis per Lumen Naturale, was published in 1683 as part of Renati Des-Cartes Musicae compendium (Blaviana printing house, Amsterdam) and again in 1701 as part of R. Des-Cartes Opuscula posthuma, physica et mathematica (Apud Janssonio-Waesbergios, Boom et Goethals, Amsterdam); it was also included in a Dutch translation of a collection of letters from Descartes published in 1684 by J.H. Glazemaker.

A definitive edition, containing the partial French text plus the fuller Dutch and Latin translations on facing pages was published in 2002. The opening passage (translated by Norman Kemp Smith to English in 1957) "is a helpful commentary on the argument of Articles 74-78" of The Passions of the Soul.