TILE COURSE OF DUMAN DEVELOPMENT. The fundamental fact that human generations are not closed cycles, but that each springs from the culminating portion of the last, cannot be too strongly emphasized; it. follows that human de velopment is progressive. While it would be premature to attempt final analysis of the ele talents in this progression, it is easy to trace the general course, which lies in the direction of increasing mentality. A similar tendency seems to affect animal and vegetable life. and may per vade all nature; yet it is so especially character istic of the human realm as first to distinguish man from lower animals, and then to afford a basis for classifying mankind.
While the dominant factor of human progress is mentality, the psychic forces must interact with the physical forces concerned in bodily growth and heredity and progressively shape both functions and so that, e.g. cranial capac ity increases amiprognathism decreases from the louver races to the higher and from primitive culture to enlightenment.
In the domain of mind the progressive tend ency is conspicuous. Gallatin and Turner were led to the study of aboriginal languages largely as indices to primitive minds, which seemed to them unlike those of their own fell OW'S ; Ty 101''S conclusions as to primitive belief imply constant differences between the mental operations of tribesmen and those of peoples living in organized nations; Powell perceived that while the minds of primitive men differ from those of advanced men there are striking coincidences in the men tality of unrelated tribes, and was thereby led to the classification of peoples by stages of culture; Brinton pursued the inquiry with special refer ence to coincidences of belief among unrelated peoples, and was led to a conception of the unity of mind ; while McGee extended the observations and SUInmed them up in a of the responsivity of mind (foreshadowed by Bacon in the first Aphorism of the Norum Organum), in which the mind becomes a more or less perfect mirror of external nature, and knowledge merely an in tegration of experience with such reflections as earlier experiences may have produced.
These successive generalizations are accordant. and the last agrees with the common observation that in any human group experiences accumulate in such manner that the possession of each generation is greater than that of the last. This accumulation is itself cumulative with increasing capacity. and operates through a specific process, of which the distinctive feature resides in the fact that it involves no loss, hot constant gain. In the physical realm any mass or velocity con veyed from one body to another is lost to the first body when gained by the second, but in the realm of mentality the transmission of knowledge from one individual to another involves no loss to the giver. however great the gain to the receiver.
It follows that human knowledge is influenced by contact with individuals and groups, its aggre gate increasing in 'a geometric ratio: also that mental acquisitions once made are seldom lost, though often assimilated in complexe• combina tions in which original features may not be recog nizable; and. furthermore. that those groups of mankind possessing the greater capacity or the larger accumulation of experiences think the more congruously with both external nature and human character, i.e. their mental operations arc the more just and the more humane.
The demotic classification of mankind, or the definition by culture-grades, is an application of the principle of cumulation of knowledge, itself a corollary of the law of mental responsivity. Savagery is hut the stage of extreme provincial ism in which thought and fellow-feeling are limited to the family group and the local range, and in which (at least initially) the only knowl edge of relationship is that based on the ocular evidence of maternity; while local animals may be deemed more closely akin to the group than . alien men, and lire, certain plants, and even in organic objects are thought to possess human attributes and may be regarded as belonging to the family. So, too, barbarism is a stage of less extreme provincialism in which knowledge and sympathy extend to the tribe and its range, and perhaps to confederated tribes; through increas ing knowledge paternity is recognized and he comes the basis of a relationship from which natural objects are eliminated, though zoic tute laries are retained; and through motives of - growing humanity. modes of adopting aliens arise. Civilization arises with knowledge of neighboring regions and peoples and with recog nition of the territorial rights of neighbor:, and the stage is characterized by that fellow-feeling and mutual confidence on which civic organiza tion necessarily rests. Enlightenment was mere _ ly the natural and necessary outgrowth of ad vancing knowledge with its concomitants of justice and humanity; the transition proceeding through political or social revolution. In ac - co•dance with the principle of cumulation, the of ideas is at first nearly barren. since human mentality remains dominated by primal animal ity, yet thought gathers about beasts and other fearsome objects to form the crude zoistic sys tems found among all adequately studied sav ages; later the nuclei of thought multiply but retain the form of beliefs, ranging from zoism and pantheism to inchoate monotheism; still later theistic concepts arc refined and spiritualized and gradually put in the background of cos mogony, while explanations of phenomena are sought in natural laws; and finally conseiou: thought rises above the mechanical conditions controlling primitive life and guides action in the light of accumulated knowledge toward pre determined ends.