THE INSTABILITY OF THE HOMOGENEOUS. 431 



§ 153. Among mental phenomena it is difficult to estab- 

 lish the alleged law without an analysis too extensive for the 

 occasion. To show satisfactorily how states of conscious- 

 ness, originally homogeneous, become heterogeneous 

 through differences in the changes wrought by different 

 forces, would require us carefully to trace out the organiza- 

 tion of early experiences. Were this done it would become 

 manifest that the development of intelligence, is, under one 

 of its chief aspects, a dividing into separate classes, the un- 

 like things previously confounded together in one class — a 

 formation of sub-classes and sub-sub-classes, until the once 

 confused aggregate of objects known, is resolved into an 

 aggregate which unites extreme heterogeneity among its 

 multiplied groups, with complete homogeneity among the 

 members of each group. If, for example, we followed, 

 through ascending grades of creatures, the genesis of that 

 vast structure of knowledge acquired by sight, we should 

 find that in the first stage, where eyes suffice for nothing be- 

 yond the discrimination of light from darkness, the only pos- 

 sible classifications of objects seen, must be those based on 

 the manner in which light is obstructed, and the degree in 

 which it is obstructed. We should find that by such unde- 

 veloped visual organs, the shadows traversing the rudi- 

 mentary retina would be merely distinguished into those of 

 the stationary objects which the creature passed during its 

 own movements, and those of the moving objects which 

 came near the creature while it was at rest; and that so the 

 extremely general classification of visible things into sta- 

 tionary and moving, would be the earliest formed. We 

 should find that whereas the simplest eyes are not fitted to 

 distinguish between an obstruction of light caused by a small 

 object close to, and an obstruction caused by a large object 

 at some distance, eyes a little more developed must be com- 

 petent to such a distinction ; whence must result a vague dif- 

 ferentiation of the class of moving objects, into the nearer 

 and the more remote. We should find that such further ini- 



