STAHL, GEORG EI1NST, a celebrated German physician and chemist, was born at Anspach, October 21, 1660, studied medicine at Jena, and after practicing soccessfolly for some time, was called, in 1094, to the chair of medicine, anatomy. and chemistry, in the newly-founded university of Halle; whence he removed to Berlin in 1716, where he was ar po;mteti I hysician to the king of Prussia. He was a member of the Berlin Academy, mud died in that city Nay 14, 17:14. According to Blumenhaen, Stahl is to be considered as one of the greatest and most profound physicians the world has ever seen, thongh the mysticism with which his works are imbued is to be reprehended. Stahl's system of medicine, which was a combination of the physiology of Van Helmont (q.v.) with the psychology of Descartes, is founded upon the supposition of the existence of a mysterious force residing in, but independeut of, and superior to muffler; this force, the anima (or "soul "). um only forms the body, but directs it in the exercise of all its functions, and tins, too, sometimes unconsciously; though the way in winch this influ ence is exercised he does not explain. Being subject to error by nature, the "anima," by negligence or maladroit action, originates diseases in the body, which it then attempts to cure, through the functional action of the various Stahl held that art ought only to commence where nature had ended, and to be useful, it should follow a similar course of action; he was also of opinion that plethora, either local or general, was one of the chief causes of disease. His system of therapeutics corresponded with his patho logical principles, and was confined mostly to bleeding and the use of mild laxatives.
His psychological theory of the connection between the soul and body led him into a discussion with Leibnitz (who had falsely charged him with propounding ntaterialisn), from which he emerged victorious on the essential points of their respective theories; though Leibnitz had tile of detail. Subsequent physiologists have made Stahl's opinions the object of ridicule, though his doctrine of toe •• z.ut:aa " under the name of "vital principle" and "nature." generally adopted rct the present day; but his supercilious contempt for chemistry as a medical agent has long ceased to be generally upheld. Nevertheless, Stahl was one of the ablest chemists of his time, destroyed, in 'his usual trenchant style, numberless absurd opinions which had found their way into the science, and propounded the first theory of combustion (see Piao cisrox), which was universally accepted till the time of Lavoisier (q.v.). His works, according to Haller, number 250, but the chief are—Theoria Mediea rem (Halle, 1707, 1708. 1737). which contains his medical theory, and Zymotechnia Fundasnentalis, see. Fermentationis Theoria Generalis 1697), in which his chemical opinions are set forth. An account of his opinions is found in Haller's Bildiotheca Medkincr Practice, vol. iii.; Sprengers Ilistoi•e de to Medeeine; A. Lemoine's le Vitalisme et l'Animisme de Stahl (Paris, 1864), and numerous other works.