cu. via.] ORGANIZATION OF THE SCIENCES. 221 



is a fundamental difference between them. "While astrogeny 

 contemplates the contracting spheroid chiefly as a generator 

 of other spheroids, which are from time to time formed from 

 its equatorial belt, detached as often as the centrifugal force 

 at its equator begins to exceed the force of gravitation at the 

 same place ; on the other hand, geogeny contemplates the 

 contracting spheroid only with reference to the redistributions 

 of matter and motion going on within itself, and partly con- 

 sequent upon its cooling. Partly consequent, I say, for there 

 is one further point of difference between the two sciences. 

 Astrogeny contemplates its spheroid as a radiator of heat, 

 but neglects, as not affecting its own peculiar problems, the 

 heat which the spheroid may receive by radiation from other 

 masses. But geogeny not only studies its spheroid as a 

 radiator of heat, but includes, as of the highest importance, 

 the heat which it receives from an external source. 



In Biology also the twofold point of view is obvious, 

 according as we study structures and functions in mobile 

 equilibrium at any particular epoch, or on the other hand the 

 process of adaptation which structures and functions undergo 

 as the conditions of existence change from epoch to epoch. 

 The first of these studies gives rise to the sciences of anatomy 

 and physiology, as well as to the subsidiary science of patho- 

 logy. On the other hand Biogeny comprises embryology, 

 morphology, and questions relating to the origin of species. 

 Psychology too admits of a similar division, into the depart- 

 ment which embraces the laws of association, as geneialized 

 by James Mill and further illustrated by Mr. Bain; and 

 Psychogeny, which endeavours to interpret the genesis of 

 intellectual faculties and emotional feelings in the race, 

 and their slow modifications throughout countless gene- 

 rations. 



Finally in Sociology this principle of twofold division is 

 so manifest that for the past thirty years the distinction has 

 been currently, though too vaguely, drawn between " social 



