finds the best ways of making shoes selected for his acquisition and adapted to his ability to appropriate the purposes and ideas necessary to do the work. In like manner his growth is provided for in the home, the church, and the state. The more these institutions deliberately concern themselves with his development, the more effectual are they in promoting his acquisition of social purposes and ideas. In the selection of the curriculum and in the processes of teaching, the school deliberately undertakes to socialize the individual by giving him the best purposes and ideas which society has in store for him.

The greater the number and complexity of the purposes and ideas necessary for full participation in social life, the longer is the period of infancy, or dependence, during which they are acquired by the individual. In the comparatively simple life of primitive man, it lasted only to the earlier teens; in the complex civilization of the present, it is half again, if not twice, as long. Step by step in this advance, institutions have increased in educational importance.

That which brings the individual and the social factors together, uniting them in the development of a social person, by selecting purposes and ideas and by adapting them for acquisition by the individual, is the educational factor in human development.

VIII

Natural science explains human development as the acquiring of nerve connections which promote adjustment of the human organism to environment; and the three factors of this development as (1) the incomplete organism in which new connections between stimuli and responses can be made, (2) the racial inheritance of forms of response to stimuli, and (3) certain systems of group habits, such as education and government, which select racial forms of response and cause the developing organism to acquire them. These three factors are the physical counterparts of the individual, the social, and the educational factors, which we have considered from the teleological point of view.

Let us see how the conclusions which we have now reached from the teleological point of view are supported by the authoritative and accurate conclusions of natural science. The physical counterparts of the individual, the social, and the educational factors in human development are revealed by natural science in the explanation of this development as the acquiring of nerve connections which promote the adjustment of the human organism to the environment.

As the result of a long process of variation, natural selection, and heredity, the lower animal organisms are born with ready-made connections in the nervous system that equip them for an adjustment to environment. It is due to such inborn connections, which are the physical basis of instincts, that the spider spins its web, the bee stores its honey, and the bird builds its nest. But the advantage of being fully equipped at birth for the battle of life is dearly paid for, because this equipment can be improved only through the slow evolutionary process by which it was made. Its possibilities for variation, the first step towards improvement, are extremely limited; and any improvement can be made a permanent acquisi

tion of the species only by being fixed through physical heredity in the nervous structure of succeeding generations.

Spiders, bees, and birds have made no change in abilities and in ways of acting since the days of primitive man; but during this time men have increased their abilities and improved their ways of doing things to an astonishing degree. They have bettered their vision with the telescope and microscope, their hearing with the telephone, and their locomotion with the automobile. In spinning, men have advanced from the hand loom to the marvelously effective machinery of great factories; in providing food, they have advanced from the precarious methods used by savages to the scientific methods of the farm, the factory, and the world of commerce; they have abandoned the tent of skins and the mud hut for elaborate, luxurious homes.

How does natural science explain this advance? There comes a time when evolutionary forces, instead of fixing all connections in the nervous system during the prenatal period, form only those which are absolutely necessary for life, such as those which control breathing, crying, swallowing, and digesting. The completion of other connections between stimuli and responses takes place in the intricate automatic "switchboard" of the brain after the child is born. These acquired connections are formed in accordance with racial models, selected by the group and adapted to the nature of the organism. Thus to the slow process of direct physical inheritance is added a process of racial inheritance, through which the organism may profit by successful forms of adjustment made at any time in the race, whether by the physical ancestors of the organism or not. Furthermore, an incomplete nervous system, such as that of man, makes possible greater

variation in reactions than does the complete nervous system, such as that of the bee or the spider. Greater variation makes for rapid progress by giving a greater variety of reactions and therefore a larger possibility for successful ones, which may be fixed through the influence of natural selection.

This materialistic explanation points clearly to three essential factors in human development: (1) an incomplete organism, (2) a racial inheritance of forms of reaction, and (3) certain systems of group habits which select racial models for adjustment and cause the developing organism to acquire them. Let us examine each of these three factors. First, the incomplete organism passes through a period of infancy, during which it acquires new nerve connections needed for adjustment. As Fiske says:

It is babyhood that has made man what he is. The simple unaided operation of natural selection could never have resulted in the origination of the human race. Natural selection might have gone on forever improving the breed of the highest animal in many ways, but it could never unaided have started the process of civilization or have given to man those peculiar attributes in virtue of which it has been well said that the difference between him and the highest apes immeasurably transcends in value the difference between an ape and a blade of grass. In order to bring about that wonderful event, the Creation of Man, natural selection had to call in the aid of other agencies, and the chief of these agencies was the gradual lengthening of babyhood.1

Second, environmental influences guide the formation of the new nerve connections in the developing organism. With its inborn equipment for imitation, the immature organism acquires effective reactions under the guidance of more mature organisms, as when an apprentice reacts

1 Fiske, John, The Meaning of Infancy, 1909, page 2.

more effectively in his work through imitating his master. It acquires useful reactions also as a result of the influence of tools, books, and all sorts of things that have been made by other organisms. The connections between stimuli and responses gained under such environmental influences, which are the result of many generations of progressive racial adjustment, may appropriately be called a racial inheritance. As Professor Baldwin says:

The child, apart from the defective in mind or body, learns to speak, write, read, play, combine force with others, build structures, do bookkeeping, shoot firearms, address meetings, teach classes, conduct business, practice law and medicine or whatever his line of further development may be away from the three 'r's' of usual attainment — just as well as if he had received an instinct for that activity at birth from his father and mother. His father or mother may have the accomplishment in question; and he may learn it from him or her. But then both the father and mother may not have it, and he then learns it from someone else. It is inheritance; for it shows the attainments of the fathers handed on to the children; but it is not physical heredity, since it is not transmitted physically at birth. . . . It is hereditary in that the child cannot escape it. It is as inexorably his as the color of his eyes and the shape of his nose.1

Third, various systems of group habits, such as those of school and state, select racial models for adjustment and adapt them to the immature organism in such manner that nerve connections guiding effective responses to stimuli are made in the organism. These systems of group habits have been developed through a long process of evolution. This factor becomes more prominent in promoting human development as the racial inheritance becomes more complex. Without it environmental forces impinging upon the organism would be so multifarious and

1 Baldwin, James Mark, Social and Ethical Interpretations, 1906, pp. 69-70.