Mr. Spencer’s examination of “The Principles of Sociology” has led him to the belief that what holds with organic types must hold also with types of society.  Social evolution throughout the future, like social evolution throughout the past, must, while producing, step after step, higher societies, leave outstanding many lower.  Varieties of men adapted here to inclement regions, there to regions that are barren, and elsewhere to regions unfitted, by ruggedness of surface or insalubrity, for supporting large populations, will, in all probability, continue to form small communities of simple structures.  Moreover, during future competitions among the higher races, there will probably be left, in the less desirable regions, minor nations formed of men inferior to the highest; at the same time that the highest overspread all the great areas which are desirable in climate and fertility.  But while the entire assemblage of societies thus fulfils the law of evolution by increase of heterogeneity,—­while within each of them contrasts of structure, caused by differences of environments and entailed occupations, cause unlikenesses implying further heterogeneity, we may infer that the primary process of evolution—­integration—­which, up to the present time, has been displayed in the formation of larger and larger nations, will eventually reach a still higher stage, and bring yet greater benefits.  As when small tribes were welded into great tribes, the head chief stopped inter-tribal warfare; as, when small feudal governments became subject to a king, feudal wars were prevented by him,—­so, in time to come, a federation of the highest nations, exercising supreme authority (already foreshadowed by occasional agreements among “the Powers"), may, by forbidding wars between any of its constituent nations, put an end to the re-barbarization which is continually undoing civilization.

When, eventually, this peace-maintaining federation has been formed, Mr. Spencer looks for effectual progress towards that equilibrium between constitution and conditions,—­between inner faculties and outer requirements,—­implied by the final stage of human evolution.  Adaptation to the social state, now perpetually hindered by anti-social conflict, may then go on unhindered; and all the great societies, in other respects differing, may become similar in those cardinal traits which result from complete self-ownership of the unit, and from exercise over him of nothing more than passive influence by the aggregate.  On the one hand, by continual repression of aggressive instincts and by continual exercise of feelings which prompt ministration to public welfare, and, on the other hand, by the lapse of restraints gradually becoming less necessary, there will be produced, in Mr. Spencer’s forecast, a kind of man so constituted that, while fulfilling his own desires, he will fulfil also the social needs.  Already, small groups of men, shielded by circumstances from external antagonisms, have been