ABSTRACT
Whether the kind of Life contemplated be that embraced by Physiology, or that of which Psychology treats, it equally consists of internal changes that mediately or immediately conform to external coexistences and sequences. The assimilative processes going on in a plant, and the reasonings by which a man of science makes a discovery, alike exhibit the adjustment of inner relations to outer relations. The correspondence between the organism and its environment, while becoming in each higher phase more specialized and heterogeneous, must ever remain, as it has been from the beginning, one and indivisible. Every form of Intelligence being, in essence, an adjustment of inner to outer relations; it results that as, in the advance of this adjustment, the outer relations increase in number, in complexity, in heterogeneity, by degrees that cannot be marked; there can be no valid demarcations between the successive phases of Intelligence.
