The Faber Book of Science (10 page)

Population, when unchecked, increases in a geometrical ratio. Subsistence increases only in an arithmetical ratio. A slight
acquaintance
with numbers will shew the immensity of the first power in comparison of the second.

By that law of our nature which makes food necessary to the life of man, the effects of these two unequal powers must be kept equal.

This implies a strong and constantly operating check on population from the difficulty of subsistence. This difficulty must fall somewhere
and must necessarily be severely felt by a large portion of mankind.

Through the animal and vegetable kingdoms, nature has scattered the seeds of life abroad with the most profuse and liberal hand. She has been comparatively sparing in the room and the nourishment necessary to rear them. The germs of existence contained in this spot of earth, with ample food, and ample room to expand in, would fill millions of worlds in the course of a few thousand years. Necessity, that imperious all pervading law of nature, restrains them within the prescribed bounds. The race of plants and the race of animals shrink under this great restrictive law. And the race of man cannot, by any efforts of reason, escape from it. Among plants and animals its effects are waste of seed, sickness, and premature death. Among mankind, misery and vice. The former, misery, is an absolutely necessary consequence of it. Vice is a highly probable consequence, and we therefore see it abundantly prevail, but it ought not, perhaps, to be called an absolutely necessary consequence. The ordeal of virtue is to resist all temptation to evil.

This natural inequality of the two powers of population and of production in the earth, and that great law of our nature which must constantly keep their effects equal, form the great difficulty that to me appears insurmountable in the way to the perfectibility of society. All other arguments are of slight and subordinate consideration in comparison of this. I see no way by which man can escape from the weight of this law which pervades all animated nature. No fancied equality, no agrarian regulations in their utmost extent, could remove the pressure of it even for a single century. And it appears, therefore, to be decisive against the possible existence of a society, all the members of which should live in ease, happiness, and comparative leisure; and feel no anxiety about providing the means of subsistence for themselves and families.

Consequently, if the premises are just, the argument is conclusive against the perfectibility of the mass of mankind … The poor laws of England tend to depress the general condition of the poor in two ways. Their first obvious tendency is to increase population without increasing the food for its support. A poor man may marry with little or no prospect of being able to support a family in independence. They may be said therefore in some measure to create the poor which they maintain, and as the provisions of the country must, in consequence of the increased population, be distributed to every man in smaller
proportions, it is evident that the labour of those who are not supported by parish assistance will purchase a smaller quantity of provisions than before and consequently more of them must be driven to ask for support.

Secondly, the quantity of provisions consumed in workhouses upon a part of the society that cannot in general be considered as the most valuable part diminishes the shares that would otherwise belong to more industrious and more worthy members, and thus in the same manner forces more to become dependent. If the poor in the workhouses were to live better than they now do, this new distribution of the money of the society would tend more conspicuously to depress the condition of those out of the workhouses by occasioning a rise in the price of provisions.

Fortunately for England, a spirit of independence still remains among the peasantry. The poor laws are strongly calculated to eradicate this spirit. They have succeeded in part, but had they succeeded as completely as might have been expected their pernicious tendency would not have been so long concealed.

Hard as it may appear in individual instances, dependent poverty ought to be held disgraceful. Such a stimulus seems to be absolutely necessary to promote the happiness of the great mass of mankind, and every general attempt to weaken this stimulus, however benevolent its apparent intention, will always defeat its own purpose. If men are induced to marry from a prospect of parish provision, with little or no chance of maintaining their families in independence, they are not only unjustly tempted to bring unhappiness and dependence upon themselves and children, but they are tempted, without knowing it, to injure all in the same class with themselves. A labourer who marries without being able to support a family may in some respects be considered as an enemy to all his fellow-labourers …

The evil is perhaps gone too far to be remedied, but I feel little doubt in my own mind that if the poor laws had never existed, though there might have been a few more instances of very severe distress, yet that the aggregate mass of happiness among the common people would have been much greater than it is at present.

I was suffering from a sharp attack of intermittent fever‚ and every day during the cold and succeeding hot fits had to lie down for several hours, during which time I had nothing to do but to think over any subject then particularly interesting to me. One day something brought to my recollection Malthus’s ‘Principles of Population’, which I had read twelve years before. I thought of his clear exposition of ‘the positive checks to increase’ – disease, accidents, war and famine – which keep down the population of savage races to so much lower an average than that of more civilized peoples. It then occurred to me that these causes or their equivalents are continually acting in the case of animals also; and as animals usually breed much more rapidly than does mankind, the destruction every year from these causes must be enormous in order to keep down the numbers of each species … as otherwise the world would have been densely crowded with those that breed more quickly … Why do some die and some live? And the answer was clearly, that on the whole the best fitted live. From the effects of disease the most healthy escaped; from enemies, the strongest, the swiftest or the most cunning; from famine, the best hunters or those with the best digestion; and so on. Then it suddenly flashed upon me that this self-acting process would necessarily
improve
the
race,
because in every generation the inferior would inevitably be killed off and the superior would remain – that is,
the
fittest
would
survive
… I awaited anxiously for the termination of my fit so that I might at once make notes for a paper on the subject.

The bird which is drawn to the water by its need of finding there the prey on which it lives, separates the digits of its feet in trying to strike the water and move about on the surface. The skin which unites these digits at their base acquires the habit of being stretched by these continually repeated separations of the digits; thus in course of time there are formed large webs which unite the digits of ducks, geese, etc., as we actually find them. In the same way efforts to swim, that is to push against the water so as to move about in it, have stretched the membranes between the digits of frogs, sea-tortoises, the otter, beaver, etc.

On the other hand, a bird which is accustomed to perch on trees and which springs from individuals all of whom had acquired this habit, necessarily has longer digits on its feet and differently shaped from those of the aquatic animals that I have just named. Its claws in time
become lengthened, sharpened and curved into hooks, to clasp the branches on which the animal so often rests.

We find in the same way that the bird of the water-side which does not like swimming and yet is in need of going to the water’s edge to secure its prey, is continually liable to sink in the mud. Now this bird tries to act in such a way that its body should not be immersed in the liquid, and hence makes its best efforts to stretch and lengthen its legs. The long-established habit acquired by this bird and all its race of continually stretching and lengthening its legs, results in the
individuals
of this race becoming raised as though on stilts, and gradually obtaining long, bare legs, denuded of feathers up to the thighs and often higher still.

We note again that this same bird wants to fish without wetting its body, and is thus obliged to make continual efforts to lengthen its neck. Now these habitual efforts in this individual and its race must have resulted in course of time in a remarkable lengthening, as indeed we actually find in the long necks of all water-side birds …

It is interesting to observe the result of habit in the peculiar shape and size of the giraffe (
Camelo-pardalis
):
this animal, the largest of the mammals, is known to live in the interior of Africa in places where the soil is nearly always arid and barren, so that it is obliged to browse on the leaves of trees and to make constant efforts to reach them. From this habit long maintained in all its race, it has resulted that the animal’s fore-legs have become longer than its hind legs, and that its neck is lengthened to such a degree that the giraffe, without standing up on its hind legs, attains a height of six metres (nearly 20 feet).

Lamarck really held as his fundamental proposition that living organisms changed because they wanted to. As he stated it, the great factor in Evolution is use and disuse. If you have no eyes, and want to see, and keep trying to see, you will finally get eyes. If, like a mole or a subterranean fish, you have eyes and don’t want to see, you will lose your eyes. If you like eating the tender tops of trees enough to make you concentrate all your energies on the stretching of your neck, you will finally get a long neck, like the giraffe. This seems absurd to inconsiderate people at the first blush; but it is within the personal experience of all of us that it is just by this process that a child tumbling about the floor becomes a boy walking erect; and that a man sprawling on the road with a bruised chin, or supine on the ice with a bashed occiput, becomes a bicyclist and a skater. The process is not continuous, as it would be if mere practice had anything to do with it; for though you may improve at each bicycling lesson
during
the lesson, when you begin your next lesson you do not begin at the point at which you left off: you relapse apparently to the beginning. Finally, you succeed quite suddenly, and do not relapse again. More miraculous still, you at once exercise the new power unconsciously. Although you are adapting your front wheel to your balance so elaborately and actively that the accidental locking of your handle bars for a second will throw you off; though five minutes before you could not do it at all, yet now you do it as unconsciously as you grow your finger nails. You have a new faculty, and must have created some new bodily tissue as its organ. And you have done it solely by willing. For here there can be no question of Circumstantial Selection, or the survival of the fittest. The man who is learning how to ride a bicycle has no advantage over the non-cyclist in the struggle for existence: quite the contrary. He has acquired a new habit, an automatic unconscious habit, solely because he wanted to, and kept trying until it was added unto him.

But when your son tries to skate or bicycle in his turn, he does not pick up the accomplishment where you left it, any more than he is
born six feet high with a beard and a tall hat. The set-back that occurred between your lessons occurs again. The race learns exactly as the individual learns. Your son relapses, not to the very beginning, but to a point which no mortal method of measurement can distinguish from the beginning. Now this is odd; for certain other habits of yours, equally acquired (to the Evolutionist, of course, all habits are acquired), equally unconscious, equally automatic, are transmitted without any perceptible relapse. For instance, the very first act of your son when he enters the world as a separate individual is to yell with indignation: that yell which Shakespear thought the most tragic and piteous of all sounds. In the act of yelling he begins to breathe: another habit, and not even a necessary one, as the object of breathing can be achieved in other ways, as by deep sea fishes. He circulates his blood by pumping it with his heart. He demands a meal, and proceeds at once to perform the most elaborate chemical operations on the food he swallows. He manufactures teeth; discards them; and replaces them with fresh ones. Compared to these habitual feats, walking, standing upright, and bicycling are the merest trifles; yet it is only by going through the wanting, trying process that he can stand, walk, or cycle, whereas in the other and far more difficult and complex habits he not only does not consciously want nor consciously try, but actually consciously objects very strongly. Take that early habit of cutting the teeth: would he do that if he could help it? Take that later habit of decaying and eliminating himself by death – equally an acquired habit, remember – how he abhors it! Yet the habit has become so rooted, so automatic, that he must do it in spite of himself, even to his own destruction.

We have here a routine which, given time enough for it to operate, will finally produce the most elaborate forms of organized life on Lamarckian lines without the intervention of Circumstantial Selection at all. If you can turn a pedestrian into a cyclist, and a cyclist into a pianist or violinist, without the intervention of Circumstantial
Selection
, you can turn an amœba into a man, or a man into a superman, without it. All of which is rank heresy to the Neo-Darwinian, who imagines that if you stop Circumstantial Selection, you not only stop development but inaugurate a rapid and disastrous degeneration.

Let us fix the Lamarckian evolutionary process well in our minds. You are alive; and you want to be more alive. You want an extension of consciousness and of power. You want, consequently, additional
organs, or additional uses of your existing organs: that is, additional habits. You get them because you want them badly enough to keep trying for them until they come. Nobody knows how: nobody knows why: all we know is that the thing actually takes place. We relapse miserably from effort to effort until the old organ is modified or the new one created, when suddenly the impossible becomes possible and the habit is formed. The moment we form it we want to get rid of the consciousness of it so as to economize our consciousness for fresh conquests of life; as all consciousness means preoccupation and obstruction. If we had to think about breathing or digesting or circulating our blood we should have no attention to spare for anything else, as we find to our cost when anything goes wrong with these operations. We want to be unconscious of them just as we wanted to acquire them; and we finally win what we want. But we win unconsciousness of our habits at the cost of losing our control of them; and we also build one habit and its corresponding functional modification of our organs on another, and so become dependent on our old habits. Consequently we have to persist in them even when they hurt us. We cannot stop breathing to avoid an attack of asthma, or to escape drowning. We can lose a habit and discard an organ when we no longer need them, just as we acquired them; but this process is slow and broken by relapses; and relics of the organ and the habit long survive its utility. And if other and still indispensable habits and modifications have been built on the ones we wish to discard, we must provide a new foundation for them before we demolish the old one. This is also a slow process and a very curious one.

The relapses between the efforts to acquire a habit are important because, as we have seen, they recur not only from effort to effort in the case of the individual, but from generation to generation in the case of the race. This relapsing from generation to generation is an invariable characteristic of the evolutionary process. For instance, Raphael, though descended from eight uninterrupted generations of painters, had to learn to paint apparently as if no Sanzio had ever handled a brush before. But he had also to learn to breathe, and digest, and circulate his blood. Although his father and mother were fully grown adults when he was conceived, he was not conceived or even born fully grown: he had to go back and begin as a speck of protoplasm, and to struggle through an embryonic lifetime, during part of which he was indistinguishable from an embryonic dog, and
had neither a skull nor a backbone. When he at last acquired these articles, he was for some time doubtful whether he was a bird or a fish. He had to compress untold centuries of development into nine months before he was human enough to break loose as an independent being. And even then he was still so incomplete that his parents might well have exclaimed, ‘Good Heavens! have you learnt nothing from our experience that you come into the world in this ridiculously elementary state? Why can’t you talk and walk and paint and behave decently?’ To that question Baby Raphael had no answer. All he could have said was that this is how evolution or transformation happens. The time may come when the same force that compressed the development of millions of years into nine months may pack many more millions into even a shorter space; so that Raphaels may be born painters as they are now born breathers and blood circulators. But they will still begin as specks of protoplasm, and acquire the faculty of painting in their mother’s womb at quite a late stage of their embryonic life. They must recapitulate the history of mankind in their own persons, however briefly they may condense it.

Nothing was so astonishing and significant in the discoveries of the embryologists, nor anything so absurdly little appreciated, as this recapitulation, as it is now called: this power of hurrying up into months a process which was once so long and tedious that the mere contemplation of it is unendurable by men whose span of life is
three-score
-and-ten. It widened human possibilities to the extent of enabling us to hope that the most prolonged and difficult operations of our minds may yet become instantaneous, or, as we call it, instinctive.