34^ 



NA TURE 



\Aiigust II, 1 88 1 



In fact, the body is a machine of the nature of an army, 

 not of that of a watch, or of a hydraulic apparatus. Of this 

 army, each cell is a soldier, an organ a brigade, the central 

 nervous system head-quarters and field telegraph, the alimentary 

 and circulatory system the commissariat. Losses are made good 

 by recruits born in camp, and the life of the individual is a 

 campaign, conducted successfully for a number of years, but 

 with certain defeat in the long run. 



The efficacy of an army, at any given moment, depends on 

 the health of the individual soldier, and on the perfection of 

 the machinery by which he is led and brought into action at the 

 proper time ; and, therefore, if the analogy holds good, there 

 can be only two kinds of di-eases, the one dependent on 

 abnormal states of the physiological units, the other on pertur- 

 bation of their co-ordinating and alimentative machinery. 



?Ience, the establishment of the cell theory, in normal biology, 

 w.as swiftly followed by a "cellular pathology," as its logical 

 counterpart. I need not remind you how great an instiiiment 

 of iuvestigation, this doctrine has proved in the hands of the 

 man of genius, to whom its development is due ; and who 

 would probably be the last to forget that abnormal conditions 

 of the co-ordinative and distributive machinery of the body 

 are no less important factors of disease. 



'■ Henceforward, as it appears to me, the connection of 

 medicine with the biological sciences is clearly defined. Pure 

 pathology is that branch of biology which defines the particular 

 perturbation of cell life, or of the co-ordinating machinery, or of 

 both, on which the phenomera of disease depend. 



Those who are conversant with the present state of biology will 

 hardly hesitate to admit that the conception of the life of one 

 of the higher animals as the summation of the lives of a cell 

 aggregate, brought into harmonious action by a co-ordinative 

 machinery formed by some of these cells, constitutes a per- 

 manent acquisition of physiological science. But the last form 

 of the battle between the animistic and the physical views of 

 life is seen in the contention whether the physical analysis of 

 vital phenomena can be carried beyond this point or not. 



There are some to whom living protoplasm is a substance 

 even such .as Harvey conceived the blood to be, "summacum 

 providentia et intellectu in finem certum agens, quasi ratiocinio 

 quodam" ; and who look, with as little favour as Bichat did, 

 upon any attempt to apply the principles and the methods of 

 physics and chemisti-y to the investigation of the vital processes 

 of growth, metabolism, and contractility. They stand upon the 

 ancient ways ; only, in accordance with that progress towards 

 democracy which a great political writer has declared to be the 

 fatal characteristic of modem times, they substitute a republic 

 formed by a few billion of " animulos " for the monarchy of the 

 all pervading "anima." 



Others, on the contrary, supported by a robust faith in the 

 universal applicability of the principles laid down by Descartes, 

 and seeing that the actions called " vital" are, so far as we have 

 any means of knowing, nothing but changes of place of particles 

 of matter, look to molecular physics to achieve the analysis of 

 the living protoplasm itself into a molecular mechanism. If 

 there is any truth in the received doctrines of physics, that 

 contrast between living and inert matter, on which Bichat lays 

 so much stress, does not exist. In nature, nothing is at rest, 

 nothing is amorphous ; the simplest particle of that which men 

 in their blindness are plea ed to call " brute matter" is a vast 

 aggregate of molecular mechanisms, performing complicated 

 movements of immense rapidity and sensitively adjusting them- 

 selves to every change in the surrounding world. Living matter 

 differs from other matter in degree and not in kind ; the micro- 

 cosm repeats the macrocosm ; and one chain of causation con 

 nects the nebulous original of suns and planetary systems with 

 the protoplasmic founda'ion of life and organisation. 



From this point of view, pathology is the analogue of the theory 

 of perturbations in astronomy ; and therapeutics resolves itself 

 into the discovery of the means by which a system of forces 

 competent to eliminate any given perturbation may be introduced 

 into the economy. And, as pathology bases itself upon normal 

 physiology, so therapeutics rests upon pharmacology ; which is, 

 strictly speaking, a part of the great biological topic of the 

 influence of conditions on the living organism and has no 

 scientific foundation apart from physiology. 



It appears to me that there is no more hopeful indication of 

 the progress of medicine towards the ideal of IJe; cartes than is 

 to be derived from a comp.arison of the state of pharmacology, 

 at the present day, with that which existed forty years ago. 



If we consider the knowledge positively acquired, in this short 

 time, of the modus operandi of urari, of atropia, of physostigmin, 

 of veratria, of casca, of strychnia, of bromide of potassium, of 

 phosphonis, there can surely be no ground for doubting that, 

 sooner or later, the pharmacologist will supply the physician 

 with the means of affecting, in any desired sense, the functions 

 of any physiological element of the body. It will, in short, 

 become possible to introduce into the economy a molecular 

 mechtmism which, like a very cunningly contrived torpedo, shall 

 find its way to some particular group of living elements, and 

 cause an explosion among them, leaving the rest untouched. 



The search for the explanation of diseased states in modified 

 cell life ; the discovery of the important part played by parasitic 

 organisms in the Ktiology of disease ; the elucidation of the 

 action of medicaments by the methods and the data of experi- 

 mental physiology ; appear to me to be the greatest steps which 

 have ever been made towards the establishment of medicine 

 on a scientific basis. I need hardly say they could not have 

 been made except for the advance of normal biology. 



There can be no question then as to the nature or the value 

 of the connection between medicine and the biological sciences. 

 There can be no doubt that the future of Tathology and of 

 Therapeutics, and therefore that of Practical Medicine, depend 

 upon the extent to which those who occupy themselves with 

 these subjects are trained in the methods and impregnated with 

 the fundamental truths of Biology. 



And, in conclusion, I venture to suggest that the collective 

 sagacity of this Congress could occupy itself with no more 

 important question than with this : How is medical education 

 to be arranged, so that, w ithout entangling the student in those 

 details of the systcmatist which are valueless to him, he may be 

 enabled to obtain a firm grasp of the great truths respecting 

 animal and vegetable life, without which, notwithstanding all 

 the progress of scientific medicine, he will still find himself an 

 empiric ? 



ON THE VALUE OF PATHOLOGICAL 

 EXPERIMENTS i 



A S reporter on Medical Education at the last Interr ational Medi- 

 ■^^ cal Congress held in Amsterdam, I raised the question how 

 far the experimental method is necessary to instruction ; and the 

 result at which I arrived was that the use of this method to 

 its greatest extent, and especially of vivisection, is an indis- 

 pensable means.' In a still higher measure, however, I had to 

 raise into prominence the importance of this method in research ; 

 and, in opposition to those who, with constantly increasing ve- 

 hemence, brought accusations against the experimental investi- 

 gators on account of the direction and method of their researches, 

 I was able to say, with the lively assent of the numerous 

 members of the Congress, and without one word in contradic- 

 tion: " All those who attack vivisection as a means of science 

 have not the least idea of the importance of the science, and 

 much less of the importance of this aid to knowledge." 



In the two years w hich have since passed away, the agitation 

 of the opponents has grown both extensive and important in its 

 object. One country after another has been drawn into their 

 net, and international combinations have been formed, in order 

 by united force to obtain greater re-ults. No increase of satis- 

 faction has been produced by the concessions made in 1S76 by 

 the legislation in England. Tlie demands have increased : a 

 petition from the new Leipsic Society for the Protection of 

 Animals, dated March 8 of the present year, desired of the 

 German Reichstag the enactment of a law by which "cruelty to 

 animals nnder the pretext of scientific research" should be 

 punished " with imprisonment for periods of not less than five 

 weeks to two yeai-s, and with simultaneous deprivation of civil 

 rights." All, indeed, do not go so far. Many do not demand 

 that all experiments on living animals should be at once sup- 

 pressed, but that there should be limitations, some demanding 

 more, others less. But even these do not make it secret that 

 this concession is only provisional ; and they demand that even 

 the offickal laboratories of the universities should be placed under 



^ Address given at the International Medical Congress by Rudolf Virchow, 

 M.D., Professor in the University of Berlin. The Editor of the British 

 Medical Journal has kindly allowed us to use his translation of Prof. 

 Virchow's address. 



' Congres Pifriodique International des Sciences M(£dicales, 6 Session, 

 Amsterdam (1S79). 1880. p. 146, Archi-j Hir Pathol. Aiiat., Band Ixx.xv. 

 Heft 3. 



