MODERN EVOLUTION. 195 



terday, that in which Progress essentially consists, 

 is the transformation of the homogeneous into the 

 heterogeneous" (Essays, vol. i, 1883, p. 30). 



To this may fitly follow the " succinct statement 

 of the cardinal principles developed in the successive 

 works," which Mr. Spencer, as named above, pre- 

 pared for Professor Youmans. 



1. Throughout the universe in general and in 

 detail there is an unceasing redistribution of matter 

 and motion. 



2. This redistribution constitutes evolution when 

 there is a predominant integration of matter and 

 dissipation of motion, and constitutes dissolution 

 when there is a predominant absorption of motion 

 and disintegration of matter. 



3. Evolution is simple when the process of in- 

 tegration, or the formation of a coherent aggregate, 

 proceeds uncomplicated by other processes. 



4. Evolution is compound, when along with this 

 primary change from an incoherent to a coherent 

 state, there go on secondary changes due to differ- 

 ences in the circumstances of the different parts of 

 the aggregate. 



5. These secondary changes constitute a trans- 

 formation of the homogeneous into the hetero- 

 geneous a transformation which, like the first, is 

 exhibited in the universe as a whole and in all (or 

 nearly all) its details; in the aggregate of stars and 

 nebulae; in the planetary system; in the earth as an 

 inorganic mass; in each organism, vegetal or ani- 



