558 



SCIENCE. 



[N. S. Vol. XX. No. 513. 



to shed light upon his subject, hut physics 

 and chemistry have methods peculiar to 

 themselves and that is the secret of their 

 great success. And so it should be with 

 physiology. However, when physiology 

 broke away from medicine, it ran into the 

 arms of physics and chemistry and is still 

 largely there. The early successes which 

 have attended the new venture, which, by 

 the way, is the case with every new venture, 

 led to the conception that this is the most 

 desirable, the most natural union. An 

 analysis, however, of the work in animal 

 physiology in the last few decades will show 

 the fact that the too great gravitation to- 

 wards jDhysies and chemistry prevented the 

 development in many directions of a purely 

 physiological character. 



I contend that physiology is an inde- 

 pendent science with a clear outline of its 

 domain, but it ought to direct its declara- 

 tion of independence not only towards 

 medicine, but also towards such exact sci- 

 ences as physics and chemistry. 



As to the standard of precision and ex- 

 actness to be required of physiology, let me 

 say this. Certainly no physiological prob- 

 lem can be solved with that exactness, with 

 that absolute reliability which is nov/ the 

 standard for a good many problems in 

 physics and chemistry. Above all in the 

 studies of the energies of life we lack the 

 controlling factor of synthesis. If we can 

 produce synthetically urea or sugars or 

 other dead constituents of a dead or living 

 body, we can not yet make synthetically 

 the smallest living organ of the smallest 

 homunculus. But what of it? Bach sci- 

 ence has its own degree of attainable exact- 

 ness. Physics and chemistry have one 

 standard and paleontology or geology is 

 bound to have another standard of exact- 

 ness.- There is no one standard of exact- 

 ness for all sciences. The scientific demand 

 upon work in any science is to strive for 



that degree of exactness which is attainable 

 in each specific field of investigation. 



I contend, further, that physiology ought 

 not and can not be properly developed 

 upon the basis of a morphological unit. 

 We might just as well attempt to put up 

 the mineral crystals as a basis for the 

 study of physics. 



I may say, further, that in my opinion 

 the knowledge of vital energies would 

 progress more rapidly if we would be 

 guided in our investigations by the view 

 that the actual processes in the phenomena 

 of life are of a very complex nature. The 

 desire to reduce the multiplicity of phe- 

 nomena to a few simple principles is a 

 philosophical importation of a psycholog- 

 ical origin. Certainly premature attempts 

 to offer simple interpretations for complex 

 phenomena have often been an obstacle for 

 a further development of our knowledge of 

 the actual processes. 



Physiology, however, may take some 

 useful hints from the otlier sciences. It 

 may learn from such exact sciences as 

 physics and chemistry that the exactness 

 and dignity of a science do not suffer 

 by coming into intimate contact with the 

 necessities of daily life. ,0n the contrary, 

 we find that those chapters of physics and 

 chemistry whose results found practical 

 application, are best developed. The con- 

 tact of a science with life and its actual 

 necessities works, on the one hand, as a 

 stimulus to investigation, and, on the other 

 hand, as a corrective against an indulgence 

 in mere hobbies. The experimental method 

 as such is no talisman against such scho- 

 lastic degeneration. A study of the litera- 

 ture of the last few decades will show that 

 physiology, too, could well stand such a 

 corrective. 



Physiology could also learn from mor- 

 phology that a special attention to the hu- 

 man being does not necessarily lead to a 

 neglect of the uniform study of the entire 



