ALL MEN ARE UNEQUAL

New Zealand Listener, Volume 13, Issue 321, 17 August 1945, Page 12

ALL MEN ARE UNEQUAL

"The Facts Are Pretty Obvious"

-says DR. I. L.G. SUTHERLAND in this condensation of last week’s talk in the Winter Course series from 3YA

ES: unequal. All men are unequal. Now this statement of mine contradicts several very famous pronouncements. The American Declaration of Independence, written by the great Thomas Jefferson, declared it to be a self-evident truth that "all men are created equal." This same pronouncement was made by ‘the authors of the French Revolution ‘and included in the famous slogan, "Liberty, Equality, Fraternity." The idea of human equality. has been one of the most influential notions in the modern world: no doubt about that. What then is the truth of the matter? With the aid of a little elementary psychology and elementary biology it is Now a very simple matter to demonstrate that all men are unequal. What becomes then of the famous revolutionary idea? Is it just a romantic myth? There is another possibility. The word equality may have several meanings; it may have too much meaning, or too many meanings for one word to cafry conveniently. And this is actually the case. Equality is one of those big and significant words, like freedom and jus‘tice, which are almost too rich in meaning, so that distinctions have to be made. But equality has a most significant meaning, in spite of the many facts of inequality. Now the facts of inequality are pretty obvious. Men are not equal, nor women either, in height or weight, or strength or beauty, or in intelligence or mental powers generally. And every type of inequality in body and mind

which is ours by inheritance is heightened by unequal environment and opportunity. What Makes You Blush Let us make some distinctions here and begin to look more closely at the facts. The American Declaration of Independence stated that "all men are created equal": that is, are equal by inheritance. Since Thomas Jefferson’s day a great deal has been learned about human inheritance. Ideas about heredity, or what we are born with, used to be a matter of speculation or even superstition, as well as including some truths of common observation, which were, however, unexplained, To-day, genetics, or the study of heredity, is a special branch: of science which is very active. Let me try to sum up a few of its important discoveries, It has become clear that nature compels variation and inequality. Differences dependent upon heredity show themselves at birth and. become more

apparent as development proceeds-dif-ferences in skin, eyes, ears, hair, teeth, blood, handedness, intelligence, and so on even down to the liability to blush. An unusual tendency to blush is a well-known family trait, connected with a delicate adjustment Of the small arteries in the skin and the nervous. system.

4adiots do not Diush, neither do infants. The capacity begins to show itself at about three years of age. It is peculiar to man. "Man," said Mark Twain, "is the only ahimal that blushes-or needs to. " Packets of Genes What is it that makes human beings inevitably so various? Well, apart from differences of ancestry it is a direct result of the two-parent mode of propagating the species. We know that the inheritance of a child, or of any living thing for that matter, consists finally of a large number of pairs of packets containing complex chemicals called genes. The genes determine unborn differences. Now each parent has a full set of the pairs of packets. The child for its development needs only one set of pairs, Its set is drawn at random, save that one packet is taken from each pair possessed by each parent, and the manner of drawing makes a difference. It is obvious from this that there are many thousands of different ways in which the child’s set may be made up, each yielding a child of different characteristics, though the ancestry is the same. There is no way of controlling the combinations that are te enter into a child of given parents, and there is no | Prospect that there ever will be. © This process sees to it that very few human characteristics breed true. It is

a fact that two brothers, or a brother and a sister, are more alike than two children taken at random. This is because they possess the same ancestry. But they also differ a good deal through the chance combination of characters from their two parents. It follows from all this that every human being is unique. Think about yourself. In the whole of the history of the world there has never been anyone else exactly like you, and in the whole of time to come there will never be another. This I suppose, is what is called a solemn thought, though I’m not sure whether it should make us feel proud or humble. The only way to get rid of inequalities and to produce similar individuals would be to use some other method of propagation: some method other than the two-parent method. This can be done with plants, but not so far with animals. It is, in fact, now extensively used with plants. A seedling tree is thought to be a good one. It is therefore multiplied, not by allowing it to flower and seed, that would mean variations, but by cutting and grafting. The trees derived in this way are all extraordinarily alike, because they are really sections of a single tree. The usual process of propagation and the inevitable differences it produces have been side-tracked. The several million trees of Cox’s Orange Pippin in the world are really a single individual. If one were allowed to flower and seed there would be differences at once. Human Beings from Cuttings? As yet we cannot propagate human beings from cuttings. King Solomon’s suggested experiment in this direction was abandoned, you will remember, because of opposition from the mother of the subject. The idea of propagating human beings from cuttings is rather intriguing. From whom would we cut and graft and why? But until the art of tissue culture has developed very considerably it is, perhaps fortunately, out of the question. Hence, as one authority states, "so long as bi-parental inheritance is kept up, the variety, the surprises, the perplexities, the melodrama, that now present themselves among the fruits of the human vine, will continue." Curiously enough,. however, Nature occasionally carries out King Solomon’s experiment and so produces a few exceptions to the almost universal law of difference. At about four births in every 350, twins are produced, Now twins may (continued on next page)

(continued from previous page) be of two different sorts. Sometimes they are not very alike and may be one of each, a boy and a girl, no more alike than brothers and sisters born separ ately. In other cases twins are of the same sex and as alike as two peas or more so. In three out of four cases of twinning the first happens. Two individuals develop together and have differing inheritance, In the fourth case, however,*the human egg divides completely and two identical individuals develop. Identical Twins At the present time about two thousand pairs of identical twins are born in Great Britain every year, and a proportionate number in this country. Jacob and Esau are the classical example of twins who are non-identical. The similarity in the case of identical twins is astonishing and many strange stories are told of them, Their identity extends even to finger prints.. The right hands of a pair of identical twins are more alike as judged by finger prints than the right

and left hands of the same person. Handwriting is similar, teeth decay together, similarity in bodily and mental characteristics is pervasive and minute, Identical twins are created equal. No others are. In England at least one person in two hundred is feeble-minded; and again the proportion, if judged by the same standards, is about the same here. What could be done to reduce this unfortunate form of inequality? Something could be done by eugenics, but not nearly as much as some enthusiasts have imagined. The reason is clear. About 80 per cent. of mentally deficient children are born to parents who are apparently normal. In their case there was no known reason why they should not have normal children: but they carried some latent defect in their inheritance and it appeared in some one or more of their children, Mental defect is mainly transmitted by persons who are themselves unaffected. If every defective person were prevented from having children it would still take hun-' dreds of generations to eliminate mental defect. Environment Also Counts. Now what about. environment, or what we are born into. Well, in many things it makes what is already unequal more so. It is important to have a clear idea about the relation between heredity and environment. They are often regarded as opposed and contrasting influences. This is not so. They interact. The way the genes themselves interact and what they produce depends on the conditions, on

the environment, that is. Take the case || of stature or body height. Bodily stature has usually been regarded as mainly hereditary in origin, but it has recently been shown that living conditions can make;a big difference. Shortly before the war in the Pacific began an American scientist made a large-scale study of Japanese born in Hawaii and their own relatives and connections born in Japan. This study showed those born and brought up in Hawaii to be taller and heavier than those in Japan, a different diet being an amportant factor in bringing about this change in stature. Heredity and environment interact here. Environment can thus increase, or of course sometimes decrease, the inequalities due to heredity. .