THE OBJECTS OF PHYSIOLOGY. 19 



physical knowledge. In using this term we must not think it 

 implies a separate set of laws of life. We cannot discover or for- 

 mulate any special laws affecting living beings only, and therefore 

 we must not assume that any such exist. \Ve must rather en- 

 deavor to explain all the so-called " vital phenomena " by means of 

 the laws known to chemists and physicists. By this means we 

 shall certainly get a closer insight into the processes of life, and 

 if there be laws governing the living beings we may learn to know 

 them. This method of working has already given good results, 

 for within comparatively recent times many of the processes which 

 were regarded as specially vital in character have been shown to 

 be within the power of the experimenter and to depend on purely 

 physico-chemical processes. 



It is therefore necessary for the physiologist, before he attempts 

 to explain the activities of any organism, to be familiar with not 

 only the structure of its body but also the various laws which, as 

 chemists and physicists teach us, control the operations of inani- 

 mate matter. 



The sciences of chemistry and physics may, in fact, be regarded 

 as the physiology of inorganic matter, just as, when chemistry and 

 physrcs are applied to the elucidations of the functions of living 

 creatures by the biologist, the study is called physiology. When 

 we consider how far the chemist and the physicist still are from 

 thoroughly grasping and interpreting all the phenomena presented 

 by the various kinds and conditions of matter, we cannot be sur- 

 prised that those who attempt to explain the actions of living be- 

 ings find many processes that they are unable to comprehend. 

 But while physiologists frequently make use of the convenient 

 term " vital phenomena," they do not thereby imply the existence 

 of a special living force or any kind of energy peculiar to living 

 creatures. 



The final end of physiology is, then, not yet within the reach 

 of our modern methods of research. To explain the mode of ac- 

 tivity of living beings, and grasp the exact relation borne by their 

 living phenomena to the laws which govern them, is a task of 

 enormous difficulty. Indeed the manifestations of certain ener- 

 gies in living organisms are so complicated that it is often, if not 



