236 Heredity. 



2. In the whole of the foregoing we have constantly spoken of 

 synthesis, integration, fusion, association. How is this operation 

 performed which reduces diversity to unity ? Does it result from 

 the elements themselves? Are these syntheses formed after the 

 manner of chemical combinations, and according to laws depen- 

 dent on the quantity and the quality of the combined elements ? 

 Must we deduce the unity of the facts of consciousness from the 

 unity of the vital phenomena, and look for the cause of mental 

 synthesis in organic synthesis ? This would scarcely help us, for 

 we know how difficult it is to explain physiological unity in the 

 living being. 



The unity of the fact of consciousness is indisputable, and, to 

 our mind, inexplicable, so long as we do not go beyond pheno- 

 mena that is to say, beyond the sphere of science. But, though we 

 here treat of the composition of the mind, we desire in no respect 

 to go beyond the phenomenology of the mind. We will, then, 

 examine the different aspects of the question from the point of 

 view of experience. 



The question which arises with regard to the unity of life arises 

 again with regard to the unity of consciousness : whether it be an 

 effect or a cause. We have seen that some physiologists, instead 

 of regarding life as a cause on which the functions depend, place, 

 on the contrary, all the reality in the functions of which vital unity 

 is only a resultant or composite effect. The same hypothesis has 

 been introduced into psychology, and it is upheld by the following 

 arguments. 



In psychology the idea of personality is fundamental, as in 

 biology is the idea of individuality. But the person, the ego, the 

 thinking subject, assumed as a perfect unity, is but a theoretic 

 conception. It is an ideal which the individual approaches as he 

 rises in the scale of being, but to which he never attains. Our 

 personality breaks up into an infinity of sensations, sentiments, 

 images and ideas, past or future ; it is only a synthesis, an aggre- 

 gate, a sum that is ever undergoing addition and subtraction, but 

 of which the whole reality is in the concrete events which com- 

 pose it. 



If we scan the whole biologic scale, we shall see that at the 

 lowest grade, where there is simply life, the phenomena and the 



