Through Nature to God

by John Fiske

This conclusion, which follows irresistibly from Wallace's theorem, that in the genesis of Humanity natural selection began to follow a new path, already throws a light of promise over our whole subject, like the rosy dawn of a June morning. But the explanation of the genesis of Humanity is still far from complete. If we compare man with any of the higher mammals, such as dogs and horses and apes, we are struck with several points of difference: first, the greater progressiveness of man, the widening of the interval by which one generation may vary from its predecessor; secondly, the definite grouping in societies based on more or less permanent family relationships, instead of the indefinite grouping in miscellaneous herds or packs; thirdly, the possession of articulate speech; fourthly, the enormous increase in the duration of infancy, or the period when parental care is needed. Twenty-four years ago, in a course of lectures given yonder in Holden Chapel, I showed that the circumstance last named is the fundamental one, and the others are derivative. It is the prolonged infancy that has caused the progressiveness and the grouping into definite societies, while the development of language was a consequence of the increasing intelligence and sociality thus caused. In the genesis of Humanity the central fact has been the increased duration of infancy. Now, can we assign for that increased duration an adequate cause? I think we can. The increase of intelligence is itself such a cause. A glance at the animal kingdom shows us no such thing as infancy among the lower orders. It is with warm-blooded birds and mammals that the phenomena of infancy and the correlative parental care really begin.

VII
The Chief Cause of Man's lengthened Infancy

The reason for this is that any creature's ability to perceive and to act depends upon the registration of experiences in his nerve-centres. It is either individual or ancestral experience that is thus registered; or, strictly speaking, it is both. It is of the first importance that this point should be clearly understood, and therefore a few words of elementary explanation will not be superfluous.

When you learn to play the piano, you gradually establish innumerable associations between printed groups of notes and the corresponding keys on the key-board, and you also train the fingers to execute a vast number of rapid and complicated motions. The process is full of difficulty, and involves endless repetition. After some years perhaps you can play at sight and with almost automatic ease a polonaise of Liszt or a ballad of Chopin. Now this result is possible only because of a bodily change which has taken place in you. Countless molecular alterations have been wrought in the structure of sundry nerves and muscles, especially in the gray matter of sundry ganglia, or nerve-centres. Every ganglion concerned in the needful adjustments of eyes and fingers and wrists, or in the perception of musical sounds, has undergone a change more or less profound. The nature of the change is largely a matter of speculation; but that point need not in any way concern us. It is enough for us to know that there is such a change, and that it is a registration of experiences. The pianist has registered in the intimate structure of his nervous system a world of experiences entirely foreign to persons unfamiliar with the piano; and upon this registration his capacity depends.

Now the same explanation applies to all bodily movements whatever, whether complicated or simple. In writing, in walking, in talking, we are making use of nervous registrations that have been brought about by an accumulation of experiences. To pick up a pencil from the table may seem a very simple act, yet a baby cannot do it. It has been made possible only by the education of the eyes, of the muscles that move the eyes, of the arm and hand, and of the nerve-centres that coordinate one group of movements with another. All this multiform education has consisted in a gradual registration of experiences. In like manner all the actions of man upon the world about him are made up of movements, and every such movement becomes possible only when a registration is effected in sundry nerve-centres.

But this is not the whole story. The case is undoubtedly the same with those visceral movements, involuntary and in great part unconscious, which sustain life; the beating of the heart, the expansion and contraction of the lungs, the slight changes of calibre in the blood-vessels, even the movements of secretion that take place in glands. All these actions are governed by nerves, and these nerves have had to be educated to their work. This education has been a registration of experiences chiefly ancestral, throughout an enormous past, practically since the beginnings of vertebrate life.

With the earlier and simpler forms of animal existence these visceral movements are the only ones, or almost the only ones, that have to be made. Presently the movements of limbs and sense organs come to be added, and as we rise in the animal scale, these movements come to be endlessly various and complex, and by and by implicate the nervous system more and more deeply in complex acts of perception, memory, reasoning, and volition. Obviously, therefore, in the development of the individual organism the demands of the nervous system upon the vital energies concerned in growth must come to be of paramount importance, and in providing for them the entire embryonic life must be most profoundly and variously affected. Though we may be unable to follow the processes in detail, the truth of this general statement is plain and undeniable.