1893.] 



Pathology among Biological Studies. 



125 



constituent parts, which is in its tnrn the first axiom necessary for 

 the study and the understanding of life. 



A long time, however, elapsed before it was possible to return 

 to this starting point, and to obtain a considerable number of 

 supporters for the doctrine of the " vita propria." The attention of 

 many observers was drawn to a totally different side of the question. 

 In the last decade of the past century, about the same time that John 

 Hunter, starting from careful anatomical investigations and exact 

 observations of surgical practice, worked out his idea of the material 

 of life, a new system of medicine was founded in Scotland, the so- 

 called Brownian system, which was based on quite different pre- 

 misses. Brown also was a vitalist ; he, too, constructed, not merely 

 a pathological and therapeutic system of vitalism, but a physio- 

 logical one, though this doctrine was dynamic in its character. 

 There is but little to be noticed therein of the material anatomical 

 foundation of exact medicine. It is principally concerned with 

 contemplations of the forces of the living organism. One can under- 

 stand to some extent how this happened, if the history of the deve- 

 lopment of this extraordinary personality is kept in view ; I cannot 

 go into this here, but anyhow the remarkable fact remains that the two 

 contemporaries, Brown and Hunter, worked near each other without 

 any evidence in their writings that they were acquainted with one 

 another. Brown struck out his own line, and stuck to it, without 

 troubling himself about the rest of the medical world. And yet even 

 his first work, ' Elementa Medicinae,' had the effect of an earth- 

 quake ; the whole European continent was shaken by it, while the 

 physicians of the recently opened New World bent under the yoke of 

 revolutionary ideas ; and in a few years the aspect of the whole field 

 of medicine was entirely changed. True, the triumph was but short ; 

 the Brownian system disappeared as it had come, a meteor in the 

 starry heaven of science. There would be no reason to go into it more 

 fully, had not the impulse which it gave stimulated other men, 

 by whom it was permanently applied to the true service of science. 

 This impulse was founded on the fact that irritability, or, as Brown 

 called it, " incit ability," was thus reinstated as the starting point of 

 the theory ; but, along with this, the stimuli which set living substances 

 in action, the " potestates incitantes," were brought to the fore. In 

 so far as stimuli produce a state|of irritation (" incitatio "), or, as 

 Brown called it later, excitement, they came to be viewed not only 

 as the cause of health and disease, but even of life itself ; for excite- 

 ment, so he said, is the true cause of life. But, as excitement stands 

 in a certain relation to the strength of the stimulus, a state of goo4 

 health was only possible with a normal degree of stimulus, whilst an 

 excess or a lack of stimulus brought diseased conditions in its wake. 

 Of course excitement is dependent also on irritability, with a certain 



