1893.] Pathology among Biological Studies, 117 



since the time of Hippocrates, it had been the custom to use, 

 instead of life, the obscure expression 0i/<rt9, natura ; but it is 

 vain to seek for a more exact definition of the term. To Paracelsus 

 nature was living, and the basis of his life was that very "archaeus," 

 a force differing* from matter, and separable from it, or, as he himself 

 expressed it, in the sense of the Arabs, a spirit, "spiritus." In the 

 compound organism of man, the mikrokosmos, each part, according* 

 to him, had its own "archaeus," but the whole was ruled by the 

 " archaeus maximus," the " spiritus rector." Prom this premiss has 

 proceeded that long succession of vitalistic schools, which, in ever- 

 changing forms, and with ever new nomenclature, introduced into 

 the notions of physicians this idea of a fundamental principle of 

 life. 



If the sagacious George Ernest Stahl, whose services to the develop- 

 ment of chemistry are now universally acknowledged, substituted 

 the soul for the " spiritus rector," and so created a system of animism, 

 the last vestiges of which have only within our own time disappeared 

 from the school of Montpellier, so also in turn did the pure vitalists 

 build up on the dogma of specific dynamic energies, maintained so 

 stoutly by the physicists, that notion of the vital force, the half 

 .spiritualistic and half physical character of which has contributed so 

 much, even in our day, to puzzle and mislead men's minds. 



The doctrine of the vital force found its strongest support in the 

 " Natur-philosophie," especially in that which, on German ground, 

 soon obtained universal sovereignty. 



This summary exposition of mine has greatly anticipated the 

 historical progress of the evolution of medicine. It is now time to 

 pay proper homage to the great investigator who made the more 

 exact method the ruling one, and at the same time to award to this 

 country, which brought him forth, its important share in determin- 

 ing the new direction of our science. 



Nearly 100 years had passed since Vesalius and Paracelsus had 

 begun their work when William Harvey published his ' Exercitatio 

 anatomica de motu cordis et sanguinis in animalibus.' Here, for the 

 first time, the anatomical examination of living parts was carried 

 through, in an exemplary way, according to experimental methods- 

 All the objections founded on the doctrine that anatomy concerned 

 itself with dead parts only were thus at once set aside ; living action 

 became the object of immediate observation, and this was done on one 

 of the most important organs, one absolutely necessary to life, the 

 varying activity of which constantly calls for the attention of the 

 practical physician. Not only so, but a new mode of observation — 

 the experimental method — was thus brought into use for research ; a 

 method by means of which a new branch of medical science, physio- 

 logy, has been laboriously built up. 



