THE RELATIONS OF PHYSIOLOGY 407 



nature. Physiology can never be anything else than physics and 

 chemistry, that is, the mechanics, of living beings. 



It does not appear to be superfluous to warn here against one of 

 the consequences which may occur from a short-sighted exaggera- 

 tion of this conception of physiology. The aim of all the so-called 

 exact sciences is, admittedly, the demonstration of laws in mathe- 

 matical form. We occasionally meet with the view that, in the 

 exact natural sciences, nothing shall be the object of investigation 

 which cannot be measured according to mass and number. This 

 conception is destined to hinder the development of scientific 

 knowledge, as the first step toward the explanation of many phe- 

 nomena can, in most cases, only be made by qualitative and not 

 quantitative investigations. A weighing and measuring, a numerical 

 demonstration, is often only possible after a certain number of 

 qualitative communications have been made, and physics and chem- 

 istry have seldom arrived at great and accurate results without 

 this pioneer work. In physiology the relationships are still more 

 complex, as here we have to do with the most intricate system of 

 processes which we know of in nature, and in large part the first 

 work has yet to be done. Here, there is still less often the possibility 

 of a determination according to mass and number, and, therefore, 

 if we throw aside in hasty blindness the study of qualitative relation- 

 ships, we cast away, ourselves, the place on which we must set our 

 feet firmly before we can climb higher. Physiology must still leave 

 a large place for qualitative investigation, although the ideal goal is 

 mathematical demonstration of the processes in the living organism, 

 from which we are still far removed. It would be extremely ridicu- 

 lous to attempt to determine a definite method for physiologic 

 investigation. All schemes will do harm. Every means, every 

 method, must be welcomed, if we wish to make even a small step 

 forward. Therefore, physiology is not merely limited to the methods 

 of physics and chemistry, but will always seek after the peculiar 

 methods which are required by its special problems, although the 

 problem of physiological investigation is only the mechanical analy- 

 sis of life. 



Man is for man the most interesting object of study. No wonder 

 that the analysis of life was begun directly upon man, without con- 

 sidering that he is the most complicated and most difficult of all 

 objects. The beginnings of sciences are never systematic, as their 

 methods, problems, and aims are only seen in the course of their 

 development. Thus it was seen later that mechanical analysis of the 

 phenomena of human life could only be reached by investigating 

 and analyzing analogous phenomena in other living objects, in the 

 simplest forms. Geniuses did this earlier, of course. Harvey, Leeu- 

 wenhoek, Swammerdam, Malpighi, Redi, and others, are among the 



