Thomasius, Christian

Thomasius, Christian (1655-1728): German philosopher and jurist.

Born and educated in Leipzig as well as in the University of Frankfurt, where in 1679 he took his degree in law, Thomasius practiced as a private lecturer there, forgoing usual custom by lecturing in the vernacular instead of Latin, until he was in 1690 eased out. This was because of his criticism, through the periodical Monatsgespräche (Monthly Discourses), which he founded, of prevalent systems of church government, and his advocacy of religious toleration. Finding neighboring Brandenburg more congenial to his views, Thomasius became in 1694 the founding Professor of Law in the new University of Halle and was its President from 1710 until his death. Thomasius’ philosophical interests were many and three phases of his philosophical thought may be distinguished. His first major undertaking, in the 1680s, was to complete the project, chiefly begun by Samuel von Pufendorf, of founding natural law on human reason as distinct from theology. This led to two substantial works on the pedagogy and practice of reason, Institutiones jurisprudentiae divinae and Introductio ad philosophiam aulicam, both published in 1688. These disavowed factionalism between contemporary philosophical schools and completely subsumed morality under natural law rather than religion (though Thomasius was within another four years to see morality instead as based more on individual love than social dimension). The Introductio in particular suggested a model for an ideal state based on the law of reason. In the 1690s Thomasius continued this thread while broadening his interests still further, developing his preference for practical over abstract philosophy. Between 1694 and 1705, he fell under Pietist influence. This period marked his works on metaphysics, especially Versuch vom Wesen des Geistes (1699), which introduced his brand of mysticism in relation to questions of ontology and revelation (though this mysticism was sourced not only in Pietism but also in other philosophies and natural science). After 1705 Thomasius’ mature philosophy dealt with the place of morality and will in a deterministic world. His final major work in this respect is Fundamenta juris naturae (1705) (he also wrote a short account of natural jurisprudence which was published in 1719). Thomasius’ real importance perhaps lies in his particular description of the human condition as being on the one hand purposeful and on the other frequently prone to error in the fulfillment of purpose, and in the theories of morals and the passions he propounded to account for this dichotomy. Because of his original, extensive and wide-ranging contributions to philosophy, Thomasius is often regarded as the first serious thinker of the Enlightenment, though he left no organized school of adherents or disciples. Many Pietists during and after his lifetime adopted his thought, which accorded very well with their belief in the origin of truth solely in divine revelation. His influence was otherwise less felt but formed an important basis for later work of Christain Wolff and Kant, Immanuel, particularly in the areas of morality and natural law.

Further Reading:

W. Schneiders, Naturrecht und Liebesethik. Zur Geschichte der praktischen Philosophie im Hinblick auf Christian Thomasius, 1995

Kevin E. Dodson