What science doesn't know

JULIAN HUXLEY

A great English man of science finds that, biologically speaking, we are ignorant, not blissful

To be able to say that we are ignorant of something is the first step toward knowledge. It is when we do not know that we do not know that we are really ignorant, that the mistakes into which that ignorance leads us are all the more enormous. We all know plenty of our acquaintances who are, or seem, lamentably ignorant of their own deficiencies; who just don't know what poetry means; who are ignorant that it is not good form to wear a bowler hat with a tail-coat; who are really unaware that philosophy is anything but a string of long words; who, in fact, are all the time "moving about in world unrealized", and in consequence, stubbing their souls against all kinds of unsuspected obstacles.

But we sometimes forget that Science, vast impersonal Science, may be in the same boat. Indeed, if the past is any criterion, it undoubtedly is. For Science has often been completely unaware of what later centuries have revealed as having been about us all the time. Electricity, until the eighteenth century, meant the peculiar and rather meaningless capacity of a few substances like amber, glass, or sealing wax, to attract scraps of paper or stuff. No one dreamed that the mariner's compass, the electric cell, and lightning, were all manifestations of this same electricity; still less that we should one day resolve the whole of matter into electrical charges and fuses. So too, the mere idea that the stars were made of the same matter as the Earth, or were other worlds like ours, never entered the heads of mediaeval men, to whom the heavens and all therein were perfect, made on a different pattern from this "sublunary sphere." In the same way, the notion that matter was not perishable, but that there was a conservation of matter and of energy throughout the universe (almost the most far-reaching conclusion of modern science) was something of which the Middle Ages and Antiquity were ignorant.

And, of course, it was just as bad in biology. What man, before the last century or so, ever conceived the fantastic notion (which afterward turned out to be true) that human beings were societies of billions of tiny units, that these billion cell-citizens took their origin from one original founder, and. most fantastic of all, that the original founder had to be produced by the chance union of two quite separate and independent cell-citizens? What man, before the microscope, dreamt of the wealth and elaboration of the world of hitherto miserable creatures, or of the incredible minuteness of them? Who, before the use of geology, had imagined a world much as it is today, but peopled with dinosaurs and flying lizards? Who had begun to imagine the real antiquity of this planet?

But enough of the past; it will serve to show that we, in the present, must be bathed in ignorances so complete that they are transparent, and yet we ignore their very existence.

To begin with a specific point, we don't know whether the sea-serpent exists or not. There are plenty of obviously mythical traveller's tales about the brute. And there are a good many stories emanating from people who seem genuinely to have seen something, but have misinterpreted what they saw, whether it was a glimpse of a sounding whale, a string of leaping porpoises simulating an enormous undulating body, or the tentacle of a giant squid coiling in uncommon likeness to a large serpent. But finally, there are some half-dozen obstinately attested cases which refuse to be explained away. Half the officers and crew of a ship of the British Navy saw it. in mid-ocean; a school mistress saw it off the coast of New Zealand; I have myself met a young man, a keen but modest naturalist, who reluctantly admitted that he had seen it near the west coast of Canada. All these independent accounts agree in giving the beast a hugely long neck with an odd, unsnake-like head—"like a cow's" as one account put it. Is it a Plesiosaurus survived from the Age of Reptiles, an hallucination, or a wholly new kind of beast? We do not know.

To turn to graver or more general matters, we are quite absurdly ignorant about Growth and its opposite number, old age and natural death. What is it that brings on old age? The wearing out of this or that organ. Yes, of course, but why do the organs wear out just when they do? Why in a man, at threescore years and ten, in an elephant at over a hundred, a dog at twelve or fifteen, a rat at three or four? It is not merely size, for a horse or deer alter twice as fast as a man, a canary or sparrow twice as slowly as a rat. The matter of which our bodies is made seems to be inevitably changing, trending age-ward all our lives: but what regulates the rate of its aging; and shall we ever find a means to reverse the hands of the clock? No one knows.

The mere fact of Growth is not so mysterious. Growth—that is to say, excess self-reproduction—is an original property of all living matter. We expect it to happen, though we do not understand its chemical machinery. But what we are blankly ignorant of is, why, in some animals, Growth stops. This happens in all the more familiar creatures—ourselves, almost all other mammals, all birds, all insects: they grow until they reach a certain size, then, for all the rest of their adult lives, they grow no more. But many lower animals know no such limitations. A fish, for instance, or a lobster, or a clam—they never stop growing. As long as they live, they continue to increase in size, though a little less each year; and the only reason that they do not all reach enormous dimensions is that old age and death step in and cut short their potentially unlimited growth. This has its inconveniences. A really old salmon or lobster may be four or five times as long—which means about a hundred times as heavy—as one which has just reached sexual maturity. Shall we ever discover why our old men do not grow twenty-five feet high, or our brides increase in weight from hundred-pound sylphs to elephantine creatures of four or five tons during their life-pilgrimage? Perhaps this is one of the things we had better not find out.

The most intriguing things we do not know are the detailed and practical applications of the things we do already know in theoretical and general terms. We know, for instance, that hormones squirted into our blood by our ductless glands are responsible for all sorts of important facts of our development. Too much thyroid gives us a nervous temperament, too little makes us placid, stupid or even moronically deficient. Too much pituitary, when young, turns us into giants. Too little of this gland keeps us miniature throughout life; too much of that other produces sexual maturity in a mere child. But we have not yet discovered ways of altering the activities of these glands so as to produce desirable and permanent effects.

The same is true of drugs. Drugs are known which will do all sorts of things to the machinery both of body and mind. Quite apart from simple things like stirring the heart, speeding the bowels, raising the bloodpressure, or lowering the temperature, there are drugs which will give increased energy or heightened sense of well-being; others which will create a pageant of visual images for the most unimaginative, and provide hallucinations for those by nature imaginative visualizers. Yet their field of action is still very limited. Many can be effectively used in combating ill-health, it is true; but when it comes to enhancing our normal powers or enlarging the range of our ordinary capacities, their action almost invariably turns out to have bad after-effects, or to be temporary.

It is the same with the contest of sex, of development, of heredity. Now that we know the machinery of sex-determination, we ought to be able to gain a practical contest of sex in ourselves and the higher animals. But the practical difficulties in the way of separating the male-determiners from the female-determiners in the microscopic population of spermatozoa have so far been insuperable.

Similarly, it is becoming clear that development could he controlled. Experimenters produce at will worms with large or with small heads, fish with only one Cyclop eye, Siamese twin salamanders, moths that are neither male nor female, but intersexual, polyps with two front ends and no hind end, and other delectable monstrosities. But how to get at the early stages of mammal or bird, tucked away within the womb or the egg; even if got at, how to contest them in desirable ways—we do not know.

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Finally there is heredity. Evolution teaches us that animals and plants can he moulded in the most far-reaching ways to fit particular needs; but though we have just discovered how to produce inveritable changes by artificial means (X-rays, to he precise) these changes are quite at random, and most of them are distinctly deleterious. I low to produce the changes we would like to get we do not know.

In short, we know enough to be vouchsafed a tantalizing vision of the possibility of controlling nature and destiny, animal and human, in accordance with our wishes. The possibility is real enough; hut the matter of translating it into activity we do not know. Thus, just at the moment when we are beginning to believe that man might really turn himself into superman, our lack of knowledge is allowing war, economic chaos, and inherited deficiency to pull him down.

I have kept to the end what is by far the most important of the ignorances of biology—our ignorance about Mind. The nature of Mind, the relation of Mind to Matter, its place in the universe, our contest over its processes —all this enormous field for research —has scarcely been touched—not because science has not wanted to tackle it, but because so far the slippery thing has eluded its methods.

When the idealist philosopher proclaims that everything is Mind, he is juggling the question out of the range of science into a realm of imaginary intellectual dimensions. When the materialist thinks he has said the last word with dicta about the brain secreting thought as the liver secretes bile, he has not begun to see what the question is. And even when the judicious physiologist, tracing the intimate mutual dependence of thought or feeling and the material processes in body or brain, proclaims that the material and mental happenings are only two aspects of one reality, he has merely stated the position from which a scientific attack might be launched, could we but find the right weapons.

Let us look a moment at this last idea and its implications. It implies that thinking and feeling, as we know them in ourselves, only happen when a particular kind of appallingly complicated material machine, the cortex of the brain, is working in a particular way. The cortex is often compared with a telephone exchange, and the cells in it with the operators; if so it is an exchange with more operators than the total human population of the Earth. It implies that any alteration to the material working of the machine. whether by fatigue or stimulating drugs, or a knock on the head, will alter the accompanying mind-pro-

cesses. But—what is often forgotten —it. also implies that if we could get directly at the mind-processes and alter them, this would alter the brain machine and its material goings-on. One and the same set of processes would appear to themselves, from the inside, as thoughts and emotions, to another observer, from the outside, as electrical and chemical happenings in a soft pinky-white mass of intricate fibrework. This double aspect view seems for the moment the only one which will square with experience. But if it is true, it has all sorts of implications. The machine in our heads was not always there; it developed out of an embryo rudiment, and, originally, from a single unorganized cell. Ten or more years ago, no such brain machines as ours were in existence; there has been unbroken continuity. There is no moment, while the human being is fashioning itself out of the microscopic egg, when you can say "That's when Mind appears"; there was no moment in evolution when you could have said that all later descendants of some living stock could think and feel, however dimly, while all its previous representatives were mere material automatons.

And what does this mean? It means, if it is true, that "Matter" and "Mind" are not really separate essences.

Perhaps some day we shall be able to find a method direct or indirect of measuring Mind; and then what may we not discover about the real nature of the universe! There may prove to be a conservation of Mind just as much as there is a conservation of Matter and of Energy. Brains may prove not to be the only machines capable of generating higbtension mind, just as batteries are not the only method of getting a respectable electric potential. There may be other intensive mind-machines in existence; or we may be able to construct them, of all kinds, some for one purpose, some for another, not necessarily all of the patterns of our own minds, any more than our ordinary machines are all built on the mechanical or chemical pattern of our own bodies. We may be able not only to prove to the full the existence of telepathy, but to harness and control it—a prospect opening possibilities of mass suggestion more appalling even than those now available through the press and organized propaganda. We may even find that intensive mind does have a strong effect upon outside matter, and produce mind-rays (or whatever you chose to call them) which will make matter turn itself into all kinds of forms according to the ideas in the mind, somewhat as the radiant energy of wireless waves across the ether is now utilized to make the material particles of air organize themselves to reproduce, all over the listening world, the original words or song that was broadcast.

Some people find it humiliating to admit ignorance; I must confess that I find it exhilarating. The Earth as a mere globe is losing its unexplored secrets and each new discovery means a new adjustment of ideas and practical living. The lure of ignorance leads to the prevention of boredom and stagnation.