1 66 THE POPULAR SCIENCE MONTHLY 



not yet closed up to the satisfaction of all the gaps in this process, but 

 its "uninterrupted" character will hardly be denied by any one to 

 whom this discussion will be of interest. We may assume that the 

 principles of uniformity and continuity in evolution have been estab- 

 lished. 



Now the general process of evolution may be roughly divided into 

 cosmic, organic and social ; and it will not be denied that organic evolu- 

 tion has succeeded cosmic, and social evolution, organic. There are 

 here presented, then, three great classes of phenomena in their genetic 

 order; and not only that, but also three great divisions of the forces 

 which occasion these phenomena, and three groups of sciences of which 

 these phenomena are the subject matter. We shall now proceed to 

 analyze the forces which produce these three kinds of evolution. 



Cosmic, or inorganic, evolution involves three kinds of changes 

 atomic, molecular and molar. There are accordingly in this department 

 of evolution three sets of causes. These causes are forces to which we 

 may ascribe the names atomic, molecular and molar. Changes which 

 take place in the organic process are vital and mental ; or, as we prefer 

 to call them and the forces which give rise to them, biotic and psychic. 

 The biotic forces are those which occasion the phenomena of life, and 

 the psychic forces those which occasion the phenomena of mind. 

 Finally, the phenomena of the social world must owe their causal re- 

 lationships to forces which may be grouped under the general term 

 social. We have, then, the forces of the phenomenal world analyzed 

 into the atomic, the molecular, the molar, the biotic, the psychic, and 

 the social forces. 



It is important to observe that these various kinds of forces are not 

 coeval, but have been successively brought into existence by the process 

 described by Professor Ward 4 as synergy. As a beginning of the evolu- 

 tionary process, we may assume atomic attraction and repulsion, atomic 

 collision, elective affinities that is, atomic forces, and atomic forces 

 only. Other forces had no existence in nature except as potency. It 

 seems obvious enough that there could be no molecular forces until 

 the molecule was built up, no molar forces until molecules were combined 

 in masses, no biotic or vital forces until living matter was brought into 

 existence, no psychic forces until mind appeared, and no social forces 

 until the formation of the social group. Thus the various realms of 

 forces here suggested are coeval and co-extensive with an equal number 

 of great and well-defined fields of phenomena. No phenomena without 

 change, no change without force. To these fields of phenomena we may 

 now turn our attention. 



To the changes of phenomena occasioned by atomic forces the name 

 chemical is applied. Chemical change, so the books say, is one which 



4 See Ward, ' ' Pure Sociology, ' ' p. 171 et seq. 



