CLAUBERG, JOHN (1622-1665), was born at Salingen in the duchy of Berg, and professed philosophy and theology, first at Herborn, and afterwards at Duisburg. He was one of the first who introduced into Germany the Cartesian philosophy, which he had studied under John Ray at Leyden. His philosophical works (Opera Omnia Philosophica), collected at Amsterdam by John Theodore Schalbruch, two vols. 4to, with a life of the author by John Christian Henius, show how thoroughly he appreciated the merits of the French philosopher. The most esteemed of Clauberg's works is his Logica Vetus et Nova; but he has not admitted in this collection a little work entitled Ars Etymologica Teutonum e Philosophia fontibus derivata, published by him at Duisburg in 1663, in 8vo, and which Morhof has highly commended in his Polyhistor, and Leibnitz included in his Collectanea Etymologica. This brochure was intended as the prelude to a large work, De Causis Linguae Germanicae, which, however, the projector did not find leisure or encouragement to execute. In a separate form have been collected J. Claubergii et Martini Hundii Dissertationes selectae, quibus controversia fidei adversus omnis generis adversarios explicantur, and J. Claubergii et Tobiae Andreae Exercitationes et Epistolae varii argumenti.