Page:Popular Science Monthly Volume 79.djvu/170

166 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 established.

Now the general process of evolution may be roughly divided into cosmic, organic and social; and it will not be denied that organic evolution 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 relationships 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 as synergy. As a beginning of the evolutionary 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