METHOD^ OF PHYSIOLOGICAL RESEARCH 49 



which all our medical ideas now rest — physiology is beginning to 

 develop from a science of the organ into that of the cell. But we 

 can recognise in this only the normal course of development, which 

 first takes into consideration the gross activities of the organs and 

 then pushes gradually deeper and deeper until it arrives at the 

 cell. At all times anatomy has been the forerunner of physiology ; 

 and it must be so in order to smooth the way. Just as anatomy 

 began with the organs of the body and only in the present century 

 has reached the smallest elements of the organs, the cells, with 

 the delicate morphological investigation of which the brilliant 

 advance of modern anatomy is consummated, so physiology neces- 

 sarily began with the study of the functions of the large and 

 obvious organs, and not till the present time has it been able to 

 attack the vital phenomena of the cell. We would be guilty of 

 gross ingratitude if we were to underestimate the eminent im- 

 portance of past physiological research, upon the results of which 

 we more or less constantly build. Its aims and ideas are destined 

 to lead us still farther, and its methods are indispensable. Yet, in 

 judging the course of physiological research, we cannot forget one 

 factor which controls the development of every science, the psycho- 

 logical factor of fashion. The course of every science depends 

 upon the powerful influence of great discoveries. Wherever we 

 look at the history of investigation, we find that imposing 

 discoveries, such as are represented in physiology by the work 

 of Lud^vig, Claude Bernard, du Bois-Reymond, Liebig, Pasteur, 

 Koch, and others, divert interest from other fields and cause many 

 investigators to labour on in the same direction with the same 

 methods, especially when the methods prove so unusually fruitful 

 as in the cases mentioned. Thus, definite fields of work in 

 connection with epoch-making achievements immediately become 

 the fashion, while interest flags in other fields. In the course of 

 time equalisation takes place, for every field is limited and in time 

 becomes exhausted. We have evidently arrived at such a period 

 in physiology; the science of the physiology of the organ has 

 passed the culminating-point of its development. In the course of 

 time cell-physiology also will become exhausted, and other aims 

 and methods, such as the state of the problem at the time 

 demands, will succeed it in the incessant evolution. 



For the present, cell-physiology has before it an unbounded 

 field of labour. There are, of course, investigators who, although 

 convinced of the pressing necessity of a cell-physiology, and realis- 

 ing that the cell as the seat of the vital processes must constitute 

 the object of research, nevertheless doubt whether we are at all 

 able to get at the vital mysteries in the cell. It can, therefore, 

 reasonably be asked that a way and methods be shown by which k 

 cell-physiology may be founded. Doubt of the practicability of this 

 undertaking springs chiefly from a fact which unfortunately has 



