490 



NATURE 



[March 23, 189; 



It is not necessary for the purpose of our present inquiry to 

 carry these quotations further, since they are quite, in the Para- 

 celsian sense, contemplative in their nature ; and especially as, 

 in their generalisation, they do not appear to be important for 

 the history of advancing knowledge. 



That which is full of significance for us is concerned with 

 actual life only, in the narrower sense of analytic science. It 

 was not the " principium energeticum " set up by Glisson, 

 which stimulated his successors again to take np the thread of 

 his observations, but rather this process of irritation described 

 by him, and the fundamental faculties of living matter on which 

 it depended. In this way he has really led up to a more exact 

 study of the actions of life and the properties of living matter. 



Unfortunately, there intervened a mistaken conception, which 

 led hi;-; followers again into a series of most serious errors. 

 Glisson, following on this point also the example of Van 

 Helmont, was convinced that nerves contracted when irritated. 

 He joined to this the idea that, through the contraction of the 

 nerves, or even of the brain, the fluid contained in them was 

 propelled towards the periphery. 



This notion, shared by Willis and many other physicians of 

 that time, furnishes the reason why irritability was identified 

 with contractility. Even the great master Hermann Boerhaave, 

 and after him his pupil Gaubius, the first special writer on 

 general pathology, considered sensation and motion as common 

 properties of, at all events, all the solid parts of the body. The 

 former thought it proved that hardly a single particle of the 

 body existed which was not sensitive and did not move ; and 

 thus it becomes comprehensible how Haller himself carried this 

 idea that irritability had the same significance as contractility 

 from his school days in Leyden to his professorship in Gottingen. 

 It was in this sense that he understood the irritability of the 

 muscles, and in the same sense he denied this property to the 

 nerves. 



This dispute about the irritability of muscles has continued far 

 into the present century ; its long duration becomes intelligible 

 only when we bear in mind that, without the most exact know- 

 ledge of its historical development, even the very statement of 

 the question is liable to be misunderstood. 



As a matter of fact, so far as we know, the nerves are not 

 contractile, like the muscles ; on the other hand, the muscles 

 are not only contractile, but are also irritable. Irritability and 

 contractility are not identical, even when they occur in the same 

 part. The nerve current, on the other hand, cannot be com- 

 pared with the blood stream ; it does not consist in the move- 

 ment of a fluid, but is of electrical nature, and hence there is no 

 need for its production of a contraction of the nerve-tubes. 



It was also an erroneous conclusion that every irritated part 

 contracted. Instead of contraction, secretion, or, under certain 

 circumstances, a more vigorous nutrition, may occur as the final 

 result of irritation. Hence we use a more comprehensive term 

 in order to express this final result, and call all forms of it 

 "actions." While Glisson defined all "actio propria sic dicta " 

 as "motus activus," we distinguish different kinds according to 

 the nature of the effects, or, expressed otherwise, according to 

 the direction of the activity (nutrition, formation, and function) : 

 but we agree with the above thinker in the opinion that no vital 

 energy is ever set free without stimulus : that, therefore, every 

 action is of an irritative nature. In this irritation, according to 

 my idea, consists the "principium dividendi," according to 

 which we must distinguish between active and passive processes 

 of life, and in this way we gain also a basis for the fundamental 

 division of pathological elementary processes. How much work 

 has been necessary in order to render this conception possible ! 

 And how great, even now, is the number of our colleagues who 

 have not fully accepted it ! The reason for this difficulty is two- 

 fold. 



Most of the vital actions of life, whenever they manifest 

 themselves by visible events, are of a compound nature. As a 

 rule very various, at times wholly unlike parts, each with its 

 specific energy, combine to produce them. Not unfrequently it 

 thereby happens that in the visible sum of final effects one part 

 behaves in an active the other in a passive manner. It is only the 

 most minute analysis of the phenomenon, tracing it right back 

 to the elementary parts, which allows the total result to be 

 resolved into its components ; such an analysis cannot, for the 

 most part, be expressed in current language, except at great 

 length. No language in the world is rich enough to possess 

 special expressions for each such combination. Only too often 

 we help ourselves out of the difficulty by regarding the com- 



NO. I 22 I, VOL. 47] 



pound phenomenon as a simple one, and by expressing its 

 character according to some chief trait, which stands out in a 

 commanding manner from the general picture. This is the 

 practical difficulty. 



With it, however, a theoretical difficulty is very often com- 

 bined. The human mind, owing to a natural impulse, seeks 

 in the phenomena indications of their determining cause. The 

 more complex the phenomenon the more busy is the imagina- 

 tion, in order to convert it into a simple one, and to find a 

 unitarian cause for it. So has it happened in respect to life, so 

 in respect to disease. The course of thought followed by 

 Glisson is opposed to such an explanation. He had no scruple 

 in dividing the unit of life into a large number of individual 

 lives. Although the knowledge we now possess of the arrange- 

 ments of the body was absolutely foreign to him, yet he arrived 

 quite logically at the "vita propria," the proper elementary life, 

 of the several parts. To be sure, this expression, as far as I 

 can see, is not to be found in his works, and occurs first in 

 those of Gaubius; but Glisson says distinctly (" Anatomia 

 hepatis," "Ad lectorem," N. 17): "Quod vivit per se vivit 

 vitam a nulla creatura prseter se ipsum dependentem. Hoc 

 enim verba vivere per se sonant." 



The unitarian efforts of the following period relentlessly 

 passed over the tendency of which I have just spoken. Some 

 returned to the old Mosaic dictum, " the life of the body is in 

 his blood " ; others gave the nervous system, and the brain 

 especially, the first place in their consideration. Thus once 

 more was renewed the old struggle, which for thousands of 

 years had divided the schools of medicine into humoral and 

 solidar pathology. Even when we ourselves entered on scien- 

 tific work, hsemato-pathologists stood in hostile attitude to 

 neuro-pathologists. 



In England, humoral pathology found a strong support in the 

 great and legitimate authority of John Hunter. Although this 

 distinguished practitioner never shared the one-sidedness of the 

 later pathologists, but rather attributed to the solid parts the 

 living principle the existence of which he assumed, yet, in his 

 investigations, the blood took precedence over all other parts as 

 the chief vehicle of life. 



One must, however, recall to mind that Hunter laid special 

 stress on the fact that life and organisation are not bound to each 

 other, !-ince animal substances which are not organised can 

 possess life. He started, as has already been noticed, from the 

 erroneous conception that eggs are not organised, and that it was 

 not till after incubation that the first act of organisation, namely, 

 the formation of vessels, took place. He considered his "diffuse 

 matter" (" materia vitse diffusa") as the actual carrier of life ; 

 and this was to be met with not only in the solid parts, but in 

 the blood also. This matter, according to him, existed in the 

 brain in a remarkable degree of concentration, but its presence 

 was quite independent of all nervous structures, as is shown by 

 the example of the lower animals which possess no nerves. In 

 the posthumous writings of Hunter, which Owen has collected, 

 the very striking expression "simple life" is met with, a state 

 most clearly to be recognised in plants and the lowest animals. 

 This simple life was in Hunter's view the ultimate source of all 

 living actions, pathological as well as physiological. 



Hunter was out and out a vitalist, but his materialistic vitalism, 

 so to speak, differed loto ccclo from the dynamic vitalism of the 

 German schools. If living matter existed independently of all 

 organisation, such living matter was beyond the scope of anatomi- 

 cal investigation ; but, on the other hand, if it were present in 

 non-organised parts, such as an egg, it was in itself the ultimate 

 source of the organisation which subsequently makes its appear- 

 ance in these parts. It must, therefore, to adopt a later mode 

 of expression, be of a plastic nature. Here Hunter's notion 

 fell in with that of the plastic lymph, as developed by Hewson ; 

 and it was only logical that Schultzenslein applied it to the blood 

 at last, and designated as " plasma" the material of life present 

 in the blood. In this way the formative and nutritive matter 

 necessary to physiological life as well as the plastic exudations oc- 

 curring in diseased conditions .could be attributed to the same 

 material— a highly satisfactory result in appearance, and 

 one providing a most convenient basis for interpretations. The 

 exponents of this notion had no scruples in going one step 

 further, and in providing this material of life with a technical 

 name. They called it "fibrin," Evidently this did not quite 

 correspond with Hunter's ideas, for we know of no such matter, 

 either in the egg or in the plants or the lower animals, as that to 

 which he attributed simple life ; but the necessities of pathology 



