For an answer, I turn with satisfaction to an older writer on the philosophy of history, one whose genial sympathy with the human heart glows on every page of his volumes, to Johann Gottfried von Herder.[21-3] The one final aim, he tells us, of all institutions, laws, governments and religions, of all efforts and events, is that each person, undisturbed by others, may employ his own powers to their fullest extent, and thus gain for himself a completer existence, a more beautiful enjoyment of his faculties. Thus, to the enriching of the individual life, its worth, its happiness and its fullness, does all endeavor of humanity tend; in it, lies the end of all exertion, the reward of all toil; to define it, should be the object of ethnology; and to teach it, the purpose of history. Let me recapitulate. The ethnologist regards each social group as an entity or individual, and endeavors to place clearly before his mind its similarities and differences with other groups. Taking objective facts as his guides, such as laws, arts, institutions and language, he seeks from these to understand the mental life, the psychical welfare of the people, and beyond this to reach the ideals which they cherished and the ideas which were the impulses of their activities. Events and incidents, such as are recorded in national annals, have for him their main, if not only value, as indications of the inner or soul life of the people. By the comparison of several social groups he reaches wider generalizations; and finally to those which characterize the common consciousness of Humanity, the psychical universals of the species. By such comparison he also ascertains under what conditions and in what directions men have progressed most rapidly toward the cultivation and the enjoyment of the noblest elements of their nature; and this strictly inductive knowledge is that alone which he would apply to furthering the present needs and aspirations of social life. This is the method which he would suggest for history in the broad meaning of the term. It should be neither a mere record of events, nor the demonstration of a thesis, but a study, through occurrences and institutions, of the mental states of peoples at different epochs, explanatory of their success or failure, and practically applicable to the present needs of human society. Such explanation should be strictly limited in two directions. First, by the principle that man can be explained only by man, and can be so explained completely. That is, no super-human agencies need be invoked to interpret any of the incidents of history: and, on the other hand, no merely material or mechanical conditions, such as climate, food and environment, are sufficient for a full interpretation. Beyond these lie the inexhaustible sources of impulse in the essence of Mind itself.