308 Heredity. 



Condillac's system, however, has been excellently criticized already, 

 and that by his own school. 1 But whatever its defects, we have 

 reason to be thankful that it took the wrong course, as it led 

 to finding the correct one, by suggesting the necessity of an em- 

 bryology of mind. 



In Condillac's day, the various hypotheses of naturalists with 

 regard to the fact of generation might be reduced to two chief 

 hypotheses, one holding the pre-existence of germs, and the other 

 epigenesis. 



The doctrine of the pre-existence of germs was the older, and, in 

 some sense, the orthodox hypothesis. Vallisnieri, Bonnet, and 

 Spallanzani maintained it in the seventeenth century; Haller also 

 held it It asserted that the ovum contains the animal or the man 

 already formed, though of infinite minuteness, that all beings, each 

 with its proper structure, have been contained in ova from mother 

 to mother ever since the moment of creation ; that the act of 

 generation merely gives them life and makes them capable ot 

 growth and development. 'They are,' says Maupertuis, in his 

 Venus Physique, ' only little statues, enclosed one within another, 

 like those works of the lathe in which the carver shows his skill 

 with the chisel by making a hundred boxes shut up one within 

 another.' 



The doctrine of epigenesis, on the other hand, then represented 

 by Buffon and Wolff, held that the being is formed in all its parts 

 in the act of generation. The embryologists of the nineteenth 

 century have shown that originally the germs of all organisms are 



1 Cabanis, p. 521, Peisse's Edition. It is interesting to compare Condillac's 

 rude embryology with that of the great psychologists of the present time. It 

 Is given in its completest form by Mr. Herbert Spencer in his Principles of 

 Psychology. The analysis begins with the most complex cognitions, and by 

 successive decompositions arrives at the simplest act of thinking viz. the per- 

 ception of a difference. The synthesis, a very different affair from Condillac's 

 artificial process, starts from reflex action, passing through instinct and memory, 

 and arrives at the operations of reason, sentiment, and will The author thus 

 ascends from the conditions of a psychic state to the state itself, from the lower 

 to the higher, from vague and general modes of mental activity to those that are 

 precise and more and more determinate, from the simple to the complex. The 

 comparison between the two methods is instructive ; it just marks the difference 

 between a truly scientific method and a purely verbal process. 



