The ways and means, material and immaterial, by which the native proclivities work out their ends, therefore, are forever in process of change, being conditioned by the changes cumulatively going forward in the institutional fabric of habitual elements that governs the scheme of life. But there is no warrant for assuming that each or any of these successive changes in the scheme of institutions affords successively readier, surer or more facile ways and means for the instinctive proclivities to work out their ends, or that the phase of habituation in force at any given point in this sequence of change is more suitable to the untroubled functioning of these instincts than any phase that has gone before. Indeed, the presumption is the other way. On grounds of selective survival it is reasonably to be presumed that any given racial type that has endured the test of selective elimination, including the complement of instinctive dispositions by virtue of which it has endured the test, will on its first emergence have been passably suited to the circumstances, material and cultural, under which the type emerged as a mutant and made good its survival; and in so far as the subsequent growth of institutions has altered the available scope and method of instinctive action it is therefore to be presumed that any such subsequent change in the scheme of institutions will in some degree hinder or divert the free play of its instinctive proclivities and will thereby hinder the direct and unsophisticated working-out of the instinctive dispositions native to this given racial type.