468 THE MULTIPLICATION OF EFFECTS. 



on each other ; or in the bias given by each book of power to 

 various subsequent books. The influence which a new 

 school of Painting (as that of the pre-Kaffaelites) exercises 

 on other schools; the hints which all kinds of pictorial art 

 are deriving from Photography ; the complex results of new 

 critical doctrines ; might severally be dwelt on as displaying 

 the like multiplication of effects. But it would needlessly 

 tax the reader's patience to detail, in their many ramifica- 

 tions, these various changes: here become so involved and 

 subtle as to be followed with some difficulty. 



§ 162. After the argument which closed the last chap- 

 ter, a parallel one seems here scarcely required. For sym- 

 metry's sake, however, it will be proper briefly to point 

 out how the multiplication of effects, like the instability 

 of the homogeneous, is a corollary from the persistence of 

 force. 



Things which we call different are things which react in 

 different ways; and we can know them as different only by 

 the differences in their reactions. "When we distinguish 

 bodies as hard and soft, rough and smooth, we simply mean 

 that certain like muscular forces expended on them are 

 followed by unlike sets of sensations — unlike reactive 

 forces. Objects that are classed as red, blue, yellow, &c., 

 are objects that decompose light in strongly-contrasted 

 ways; that is, we know contrasts of colour as contrasts in the 

 changes produced in a uniform incident force. Manifestly, 

 any two things which do not work unequal effects on con- 

 sciousness, either by unequally opposing our own energies, 

 or by impressing our senses with unequally modified forms 

 of certain external energies, cannot be distinguished by us. 

 Hence the proposition that the different parts of any whole 

 must react differently on a uniform incident force, and -must 

 so reduce it to a group of multiform forces, is in essence a 

 truism. A further step will reduce this truism to its lowest 

 terms. 



