Now these strongest tendencies, in the harmonious play of which natural good or perfection is said to consist, are themselves the result of the courses of conduct which have been most vigorous and successful in ancestral organisms, and they may therefore, perhaps, be taken as a survival and index of the antecedent state of human nature. The realisation--or, rather, continuation--of human nature as it has been and is, seems thus to be the ideal which empirical evolution is able to set before conduct,--with this formal modification, that, while the various impulses are, so far as possible, to have free play given them, they should be developed in a harmonious manner. It seems doubtful how far this tendency towards harmony is properly suggested by, or consistent with, evolution, which has implied a ceaseless struggle of opposing forces. At any rate, evolution does not seem competent to give any principle of relative subordination between the various impulses, such as might add reality to the formal principle of harmony. But what it is essential to lay stress on here is, that the only end which empirical evolution seems able to establish is conformity to human nature as it is--the tendencies in it which are strongest and most persistent. [Sidenote: and thus give no ideal for progress.] We thus see that the attempt to explain on empirical grounds what is meant by positing "life," or "increase and variety of life," as the end of action, is practically reduced to making the most persistent impulses of human nature the guide of conduct. But these impulses, it has been shown, are only the survival or remnant of past stages in the course of development, not anticipations of future stages: so that evolution is in this way incapable of giving an ideal of progress as the end for conduct, and the last word it seems able to give us as a guide for action is that we should tread in the places where the footprints of ancestral conduct have left the deepest impress. The ideal of such a system is summed up in the new Beatitude, "Blessed is he that continueth where he is." It is probably just because the empirical aspect of evolution seems so little able to yield an end for human conduct corresponding to the actual course of evolution--which has been progress--that no thorough attempt has been made to develop a system of morals from the principle just reached. It is true that systems have been worked out by moralists who have taken human nature as their standard, and that Trendelenburg, at any rate, expressly includes historical development in his conception of man. But both Trendelenburg and a moralist like Butler (who has as yet no conception of the gradual modifications of human character and tendencies produced by evolution) have a view of human nature essentially distinct from that which has been called the "naturalistic" view.[269] For both assume a definite rational organisation of impulses similar to that taught in Plato's analogy