It is only gradually, concomitant with the gradual maturing of the machine technology, that the systematisation of knowledge in scientific theory has come by common consent to converge on formulations of a genetic process of cumulative change. This science of the machine age is “evolutionary” in a peculiarly impersonal, indeed in a mechanistic sense of the term. In the consummate form, as it stands at the transition to the twentieth century, this evolutionary conception of genetic process is, at least ideally, void of all teleological elements and of all personality--except as personality may be concessively admitted as a by-product of the mechanistic sweep of the blind motions of brute matter. Neither the name nor the notion of a genetic evolution is peculiar to the machine age; but this current, impersonal, unteleological, mechanistic conception of an evolutionary process is peculiar to the late modern fashion of apprehending things. It goes without saying that this mechanistic conception of process has worked clear of personation and teleological bias only gradually, by insensible decay and progressive elimination of those preconceptions of personal force and teleological fitness that ruled all theoretical knowledge in the days when the principle of sufficient reason held over that of efficient cause; and it should likewise be a matter of course that this shift to the mechanistic footing is by no means yet complete, that scientific inquiry is not yet clear of all contamination with animistic, anthropomorphic, or teleological elements; since the change is of the nature of habit, which takes time, and since the discipline of modern life to which the mechanistic habit of mind is traceable is by no means wholly consistent or unqualified in its mechanistic drift. Yet so far has the habituation to mechanistic ways of thinking taken effect, and so comprehensive and thorough has the discipline of the machine process been, that a mechanistic, unteleological notion of evolution is today a commonplace preconception both with scientists and laymen; whereas a hundred years ago such a conceit had intimately touched the imagination of but very few, if any, among the scientific adepts of the new era.