The Science of Human Nature

in our minds the idea of causality. According to the view of all modern science, everything has a cause. Nothing is uncaused. One event is the result of other previous events, and is in t

as well. The animals and plants that exist to-day are the descendants of others that lived before. There is pr

w upon the earth, no one can doubt, for the different forms certainly show different degrees of mentality. According to the evidence of those scientists who have studied the remains of animals found in the earth's crust, there is a gradual development of animal forms shown in successive epochs. In the

s passed through many stages of development from the appearance of life upon the earth to the present time. Among the lower forms of animals to-day one sees evidence of very simple minds. In am?bas, worms, insects, and fishes, mind is very simple. In birds, it i

e of the development of mind on the earth similar to the development of animals in the past, let him think of the development of mind in the individual. There can certainly be no doubt of the development of

rmerly looked upon the world as static, a world where everything was fixed and final. Each thing existed in itself and for itself, and in large measur

lf. He has been produced by this world, and to live in it he must meet its every condition and change. We must, then, look upon human nature as something coming out of the past and as being influenced every moment by the things and forces

serious effects on the child, producing all sorts of disorders. If a child cannot hear well or is entirely deaf, many serious consequences follow. In fact, every condition or characteristic of a child that is in any way abnormal may lead on to other conditions and characteristics, often of a serious nature. The growth of adenoids, for example, may l

nce of the facts that have been enumerated? It is of great consequence to our thinking when we come to recognize fully

stimulated by a nerve current. Tiny nerve fibrils penetrate every muscle, ending in the muscle fibers. The nerve-impulse passing into the fibers of the muscles causes them to contract. The nerve s

ring causes to bear upon a child and change the child. It is possible to build up ideas, ideals, and habits. And ideas, ideals, and habits constitute the man. Training is possible only because a child is a being that can be influenced. What any child will be when grown depends upon what kind of child it was at the beginning and upon the influences that affect it during its early l

ts new meaning into our notion of the nature of a child. We can understand man only when we view him genetically,

can we understand this? There is no way of understanding such actions until we come to see that the children and men of to-day are such as they are because of their ancestors. It has been only a few generations, relatively speaking, since our ancestors were naked savages, killing their enemies and eating their enemies' bodies. The civiliz

bad, in the sense that the nature which he inherits from the past fits him better for the original kind of life which man used to live than it does for the kind of life which we are trying to live now. This view makes us see that training a child is, in a very true sense, making him over again. The child must be trained to subdue and control his original impu

ry much a savage. In the absence of training, all children are much alike, and all alike bad from our present point of view. The chief differences in children in politeness and manners generally, in morals, in industry, etc., are due, in the main, to differences in training. It is a great help merely to know how difficult the task of trainin

l development. Indeed, racial development would be impossible without heredity in the individual. The individual mu

extent their responses are alike when the individuals are placed in the same situation. A robin is like the parent robins in size, shape, and color. It also hops like the parent birds, sings as they do, feeds as they do, builds a simi

e children of human beings are human. Not only is this true, but the offspring of horses are of the same stock as the parents. Not only are the colts of the same stock as the parents, but they resemble the parents in small details. This is also true of human beings. We expect a child to be not only of the same race as the parents,

impossible to resemble both. One cannot, for example, be both short and tall; one cannot be both fair and dark; one cannot be both slender and heavy; one cannot have both brown eyes and blue. In some cases, the child resembles one

nt. If we go back only seven generations, covering a period of perhaps only a hundred and fifty years, we have one hundred and twenty-eight ancestors. If we go back ten generations, we

lacking in some of them. His neighbor may be lacking in quite different ones. Now one parent transmits to the child a certain combination of unit characters; the other parent, a different combination. These characteristics may not all appear in the child, but all are transmitted through it to the next generation, and

eely cross-fertilized, it turns out that one fourth of it will be white and three fourths yellow. But this yellow consists of three parts: one part being pure yellow which will breed true, producing nothing but yellow; the other two parts transmit white and yellow in equal ratio. That is to say, these two parts ar

g generations, and will appear pure, just as if it had not been crossed with something different. The first offspring resulting from the cross-known as hybrids-may show either one or the other of the diverse characteristics, or, when such a thing is possible, even a

ppearing is said to be recessive. In our example of the yellow and white corn, yellow is dominant and white recessive. And it must be remembered that the white corn that appears in the second generati

y lead one to expect this to be the case. Most of the experiments have been with lower animals and with plants, but recent experiments and statistical studies show that Mendelis

tle has been done that bears directly upon the transmission of mental characteristics. But our knowledge of the dependence of mind upon body shou

genius, and studies of the transmission of mental defects and defects of sense organs. The results of all these studies indicate the inheritance of mental characteristics in the same

nded, the other being normal, all of the children will be normal, just as all of the corn, in the first generation after the crossing, was yellow. But these children whose parents are the one normal and the other feeble-minded, while themselves normal, transmit feeble-mindedness in equal ratio with normality. It works out as f

children will be normal. If the children, in the last case, marry others like themselves as to origin, one fourth of their offspring will be feeble-minded. If such hybrid children marry feeble-minded persons, o

ttention, temperament, etc. Before we can speak with any certainty here, we must make very careful experimental studies of these ment

better than they would be without such training, this training does not improve the stock. The improvement of the stock can be accomplished only thr

receives them. They must be impressed by training on the next generation or that generation will receive no influence from them. The characters which we acquire in our lifetime seem not to be transmitted to our children, except through what is known as social heredity, which is merely the taking on of

n it. Heredity sets a limitation for us, fixes the possibilities. The circumstances of life determine what we will do with our inherited abilities and characteristics. Hereditary influences incline us to be tall or short, fat or lean, light or dark. The characteristics of our memory, association, imagination, our learning capacity, etc.,

far as we have any evidence, the native stocks are the same in the two cases, but in New England the influences turn men into the direction of science, art, and literature. E

times it doubtless does. But pugnacity and perseverance are not necessarily connected with intellectual genius.

ainting, others in music, others in mechanical invention, some in literary construction. When it is found that this ability is undoubtedly a native gift and not a passing whim, special opportunity should be provided for its development and training. It will be better for the general welf

. Human beings live in this world of natural law and are subject to it. Human life is completely within this world of law and

ne of the pure transmission of unit characters. Eugenics is the science of improving the human race by selective br

EXER

of animals. You can get information on

different geological epochs

lower animals and in man. What is the significance

e in animals? Does natural selection still operate a

gy, learn about the different classes of a

can learn about heredity. Enumerate all the

characteristics as height, weight, shape of head, shape of nose, hair and

ete outline

S FOR CLA

edity in Relat

cial Direction of