CORPOREAL LIFE AND SOUL LIFE 9 



explanation of phylogeny, or whether, besides it, external or in- 

 ternal causes are active, remains a question. 



According to another theory (Lamarckian), any influence acting 

 continually upon the descendants of an organism so as to produce 

 the same changes will result . in a change in the structure and 

 functions of the organism, and this change is inherited. In this 

 manner a new species originates. 



Some authors assume that there is present in the living substance 

 a fixed tendency to develop and perfect itself. 



4. CORPOREAL LIFE AND SOUL LIFE 



The problem of Physiology is the investigation of the 

 objectively demonstrable processes of life. Besides these 

 there are processes which can be perceived subjectively only. 

 These are the phenomena of soul life, the conditions and 

 processes of consciousness. The investigation of soul life is 

 the province of Psychology. 



Psychical processes are always accompanied by and 

 dependent upon physiological processes in the central 

 nervous system. The study of the character of the physio- 

 logical processes which are associated with the psychical 

 is, of course, a problem of Physiology. Hence, in the 

 study of the central nervous system and sense-organs, the 

 physiologist cannot ignore the facts of psychology, even 

 though it is not his aim to explain the psychical phenomena. 



Corresponding to the chief phenomena of life we may 

 divide human physiology into the following parts: 



1. Metabolism. 



2. The transformation and setting free of energy. 



3. Reproduction and development. 



