198 THE GENESIS OF SCIENCE. 



of the earliest of those inosculations between the diverging 

 branches of science, which are afterwards of perpetual occur 

 rence. 



Indeed, as this observation suggests, it will be well, be 

 fore tracing the mode in which exact science finally emerges 

 from the merely approximate judgments of the senses, and 

 showing the non-serial evolution of its divisions, to note 

 the non-serial character of those preliminary processes of 

 which all after development is a continuation. On re-con 

 sidering them it will be seen that not only are they diver 

 gent growths from a common root, not only are they sim 

 ultaneous in their progress ; but that they are mutual aids ; 

 and that none can advance without the rest. That com 

 pleteness of classification for which the unfolding of the 

 perceptions paves the way, is impossible without a corre 

 sponding progress in language, by which greater varieties 

 of objects are thinkable and expressible. Ou the one hand 

 it is impossible to carry classification far without names by 

 which to designate the classes ; and on the other hand it 

 is impossible to make language faster than things are classi 

 fied. 



Again, the multiplication of classes and the consequent 

 narrowing of each class, itself involves a greater likeness 

 among the things classed together ; and the consequent ap 

 proach towards the notion of complete likeness itself allows 

 classification to be carried higher. Moreover, classification 

 necessarily advances pari passu with rationality the clas 

 sification of things with the classification of relations. For 

 things that belong to the same class are, by implication, 

 things of which the properties and modes of behaviour 

 the co-existences and sequences are more or less the same ; 

 and the recognition of this sameness of co-existences and 

 sequences is reasoning. Whence it follows that the advance 

 of classification is necessarily proportionate to the advance 

 of generalizations. Yet further, the notion of likeness, botb 



