The Psychological Consequences of Heredity. 3 1 7 



metamorphosis by heredity. Though we do not mean to give 

 any advantage to this theory, still we must observe that thought 

 is impossible except with the aid of certain forms to serve as 

 schemata ; that if these forms are annexed to a certain state of the 

 brain, as is probably the case, and if this state of the brain is itself 

 the result of a gradual evolution, then the conclusion is all but 

 inevitable that the forms of thought are the result of an evolution 

 in the species. Gratiolet, whose immaterialism (spiritualism^) has 

 never been called in question, used to say that to him ' it was 

 evident that the ontological analysis of philosophers, and especially 

 that prime distinction between the ideas of time and space, were 

 inscribed in advance among the preordinations of the animal 

 organism.' Admit evolution also, and development has nearly 

 gained its cause. 



On this hypothesis, thousands and thousands of years rolled 

 away before thought could appear on earth. Neither animals un- 

 provided with a nervous system (bryozoa), nor those whose ganglia 

 are nearly independent of one another (asterias), nor those in which 

 there is just a beginning of unity, could have arrived at conscious- 

 ness : their physical life must be a confused state in which the 

 subject is not distinguished from its object. It is only in the 

 higher animals, and perhaps in man alone, that the brain, resulting 

 from a gradual evolution, and shaped by countless actions and 

 reactions which have been preserved and transmitted by heredity, 

 could become the instrument of thought. 



Thus the doctrine of development rigorously applies to the 

 world of thought the same hypothesis as to the world of life. On 

 the one hand, it deduces all species from three or four primitive 

 types, or it may be from only one. On the other hand, from a 

 few very simple psychical acts, it may be from only one, it deduces 

 the endless variety of instincts and intelligences of sentiments 

 and passions. We have endeavoured to show how this hypothesis 



another in time, should think by means of figures traced in space. But even in 

 that case we should have thinking in both time and space, and not in space 

 alone. It is useless to dwell upon an hypothesis of which the verification is 

 impossible, and which, farther, is in contradiction with the essential condition 

 of thought, viz. unity. 



