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and more interdependent, not only in reference to its members, but in reference to all of its natural relationships.
CHAPTER VI.
SECTION I. THEORIES RELATING TO THE DISTRIBUTION OF THE HUMAN
SPECIES.
The human species is in constant equilibrium with itself and with its environment. This equilibrium may be considered as relatively progressive, stationary, or even retrogressive, according as the adaptation of the species to the environment harmonizes with the more and more special and complex conditions, or stands still in established relations, or abandons its conquests, returning to simpler and more general relations. In fact, an unchangeable, stationary state no more exists than absolute mutation. Movement is inseparable from every living structure. Every society recedes or progresses, maintaining at each step a static condition which corresponds with its dynamic evolution.
The relations of societies to their environments were not at first comprehended in this manner, namely, as constituting solely relations of this kind; that is to say, constituting solely static and dynamic relations. Christian philosophy, up to recent times impregnated with the metaphysical spirit, has by turns attributed either to the physical environment /. e., to the world outside of man or to man himself, considered as independent of the world, an excessive and absolute value in the search for the causes of social forms. It is notably thus that the metaphysical philosophy of history divides into two great schools. One, primarily mesological, sees in the influence of environment the cause of social phenomena; the other, especially anthropological, intro- duces into specific natures some different human varieties and, particularly into their own race, some structural and dynamic variations which show us each step in the history of societies.
Rochell, in his Introduction to the Philosophy of History (Gottingen, 1878), and after him M. L. Gumplowicz, in his Struggle of the Races, divides the history of the systematic conceptions of societies and of humanity into three phases, partly successive and partly con- comitant. The first, chiefly theological, would be represented
