432 ELEMENTARY PROBLEMS IN PHYSIOLOGY. 



(listiuguisbed teachers I have meutionetl, viz, Dr. Gaskell ami Professor 

 Heriug,* have embodied in words which have now become familiar to 

 every student. Thewoidsin question, anabolism, whicli beiug inter- 

 preted means winding up, and catabolism, running down, are the crea- 

 tion of Dr. Gaskell. Professor Hering's equivalents for these are assim- 

 ilation, which of course means storage of oxygen and oxidizable 

 materia], and disassimilatioii, discharge of these in the altered form of 

 carbon dioxide and water. But the point of the theory which attaches 

 to them lies in this, that that wonderful power which living material 

 enjoys of continually building itself up out of its environment is, as I 

 have already suggested, not autonomic, but just as dependent on occa- 

 sional and external iuflnences or stimuli, as we know the disintegrating 

 processes to be; and accordingly Hering finds it necessary to include 

 under the term stimuli not only those which determine action, but to 

 create a new class of stimuli which he calls Assimilations- Reize, those 

 which, instead of waking living mechanism to action, provoke it to 

 rest. 



It is unfortunately impossible within the compass of an address like 

 the present, to i)lace before you the wide range of experimental facts 

 which have led two of the strongest intellects of our time to adopt a 

 theory which, when looked at a priori^ seems so contradictory. I must 

 content myself with mentioniug that Hering was led to it chiefly by the 

 study of one of the examples to which I referred in my introduction, 

 namely, the color-discriminating functions of tlie retina, Dr. Gaskell by 

 the study of that very instructive class of ])henomena which reveal to us 

 that among the channels by which the brain maintains its sovereign 

 power as supreme regulator of all the complicated processes which go 

 on in the different parts of the animal organism, there are some which 

 convey only commands to action, others commands to rest, the former 

 being called by Gaskell catabolic, the latter anabolic. - - - 



I have indicated to you that although scientific thought does not, like 

 speculative, oscillate from side to side, but marches forward with aeon-, 

 tinned and uninterrupted progress, the stages of that progress. may be 

 nuirked by characteristic tendencies; and I have endeavored to show 

 that in physiology the questions which concentrate to themselves the 

 most lively interests are those which lie at the basis of the elementary 

 mechanism of life. The word life is used in physiology in what, if you 

 like, may be called a technical sense, and denotes only that state of 

 change with permanence which I have endeavored to set forth to you. 

 In this restricted sense of the word therefore, the question '' What is 

 Lifef " is one to which the answer is approachable: but I need not say 

 that in a higher sense — higher because it appeals to higher faculties in 

 our nature — the word suggests something outside of mechanism, which 

 may perchance be ifiS cause rather than its effect. 



* Herino-, Znr Thcorie Vorf/angc in der lehendiijen Snlfitanz, Prague, 18f;8, pit. 1-22, 

 Sec also a paper by I)r. Gaskell in Lmlwig's Festschrift, Loipsic, 188d, p. 115. 



