The second essay applies the theory of the first to new facts and with a new purpose. The author, having gained his case against Godwin, ceases to be the critic and becomes the social reformer. Despairing to master all the forms of evil, he confines his study to one of them in particular, the tendency of living beings to increase beyond their means of nourishment. This phenomenon is important both from its cause and from its effects. Its cause is not the action of Governments, but the constitution of man; and its effects are not of to-day or yesterday, but constant and perpetual;[[109]] it frequently hinders the moral goodness and general happiness of a nation as well as the equal distribution of its wealth.
This is the general position, which the several chapters of the essay are to expound in detail. It is not by itself quite simple. “The constant tendency in all animated life [sic][[110]] to increase beyond the nourishment prepared for it” is in one sense common to humanity with plants and animals, but in another sense is not common to any two of the three. It is certainly true of all of them that the seeds of their life, whencesoever at first derived, are now infinitely numerous on our planet, while the means of rearing them are strictly limited. In the case of plants and animals the strong instinct of reproduction is “interrupted by no reasoning or doubts about providing for offspring,”[[111]] and they crowd fresh lives into the world only to have them at once shorn away by starvation. With the exception of certain plants which ape their superiors, like the drosera, and certain men who ape their inferiors, like the cannibals, the lines of difference between the three classes of living things are tolerably distinct. The first class, in the struggle for room and food, can only forestall each other and leave each other to die; the second deliberately prey on the first and on each other; while the third prey on both the rest. But with man this “tendency to increase beyond the food” differs from the same instinct in the other two cases by more than the fact that man has larger resources and is longer in reaching his limit. The instinct is equally strong in him, but he does not unquestioningly follow it. “Reason interrupts his career,” and asks him whether he may not be bringing into the world beings for whom he cannot provide the means of support.[[112]] If he brushes reason aside, then he shares the fate of plants and animals; he tends to multiply his numbers beyond the room and food accessible to them, and the result is that his numbers are cut down to these limits by suffering and starvation. There is nothing in this either more or less contrary to the notion of a benevolent Providence than in the general power given to man of acting rationally or irrationally according to his own choice in any other instance. On the other hand, if he listens to reason, he can no doubt defeat the tendency, but too often he does it at the expense of moral purity. The dilemma makes the desire for marriage almost an “origin of evil.” If man obeys his instincts he falls into misery, and, if he resists them, into vice. Though the dilemma is not perfect, its plausibility demands that we should test it by details, and to this test Malthus may be said to have given his whole life. His other economical works are subordinate to the essay, and may be said to grow out of it. Though we cannot omit them if we would fully understand and illustrate the central work, still the latter must come first; and its matured form requires more than the brief summary which has been given in the two preceding chapters.
The body of the book consists of historical details, and particular examples showing the checks to population in uncivilized and in civilized places, in present and in past times. The writer means to bring his conclusions home to his readers by the “longer way” of induction. As this, however, was not the way in which he himself reached them, or even stated them at first, he will ask us first of all to look at the terms of the dilemma in the light of his two original postulates[[113]]—(a) food is necessary, (b) the desire of marriage is permanent. What is the quickest possible increase of numbers in obedience to the second, and of food in obedience to the first? In the most crucial of the known instances, the actual rapidity of the increase of population seems to be in direct proportion to the easy possession of food; and we can infer that the ideally rapid increase would take place where all obstacles (whether material or moral) to the getting of food and rearing of a family were removed, so that nature never needed to remonstrate with instinct. “In no state that we have yet known has the power of population been left to exert itself with perfect freedom.”[[114]] We can guess what it would be from the animal and vegetable world, where reason does not as a matter of fact interfere with instinct in any circumstances, so far as we can judge. Benjamin Franklin, in a passage quoted by Malthus in this connection,[[115]] supposes that if the earth were bared of other plants it might be replenished in a few years with fennel alone. Even as things are now, fennel would fill the whole earth if the other plants would only allow it; and the same is true of each of the others. Townsend’s goats and greyhounds on Juan Fernandez are a better instance, because not hypothetical.[[116]] Juan Fernando, the first discoverer, had covered the island with goats from one pair.[[117]] The Spaniards resolved to clear it of goats, in order to make it useless to the English for provisioning. They put on shore a couple of greyhounds, whose offspring soon caused the goats to disappear. But without some few goats to eat all the dogs must have died; and the few were saved to them by their inaccessible refuges in the rocks, from which they descended at risk of their lives. In this way only the strongest and fleetest dogs and the hardiest and fleetest goats survived; and a balance was kept up between goat food and hound population. Townsend thereupon remarks that human populations are kept down by want of food precisely in the same way.
There is nothing to prevent the increase of human numbers if we suppose reason to have no need (as in the lower creatures it has no opportunity) to interfere. To understand the situation, however, it is best not to assume the truth of this parallelism, but to take the actually recorded instances of human increase under the nearest known approaches to absolute plenty combined with moral goodness, that is to say, with a state of society in which vice is at a minimum. “In the northern states of America, where the means of subsistence have been more ample, the manners of the people more pure, and the checks to early marriages fewer than in any of the modern states of Europe, the population was found to double itself for some successive periods every twenty-five years.”[[118]] From this near approach to an unchecked increase, we infer that the unchecked would mean a doubling in less than twenty-five years (say twenty, or perhaps fifteen), and that all population, in proportion as it is unchecked, tends towards that rate of increase.
If it is difficult to find an unchecked increase of population, it is still harder to find an unchecked increase of food; for what is meant is not that a people should find their food in one fertile country with as much ease as in another, but that, for a new people, new supplies should always be found with the same ease as the old ones. Now it is not necessary to suppose that the most fertile land is always used first;[[119]] very often it might only be used late after the rest, through political insecurity, imperfect agriculture, incomplete explorations, or the want of capital; but, when it is once occupied, the question is, will it supply new food to new-comers without any limit at all? This would be an ideally fertile land corresponding to the ideally expanding population. And on some such inexhaustible increase of food an unchecked increase of population would depend, unless men became able to live without food altogether.
Malthus afterwards pointed out, in the course of controversy,[[120]] that there is strictly speaking no question here of the comparison of two tendencies, for we cannot speak of a tendency to increase food in the same sense as a tendency to increase population. Population is increased by itself; food is increased not by food itself, but by an agency external to it, the human beings that want it; and, while the former increase is due to an instinct, the latter is (in a sense) acquired. Eating is instinctive, but not the getting of the food. We have, therefore, to compare an increase due to an instinctive desire with an increase due to labour, and “a slight comparison will show the immensity of the first power over the second.” Malthus allows that it is difficult to determine this relation with exactness;[[121]] but, with the natural liking of a Cambridge man for a mathematical simile,[[122]] he says that the one is to the other as an arithmetical to a geometrical ratio,—that is to say, in any given time (say a century) the one will have increased by multiplication, the other only by addition. If we represent both the population and the food at the beginning of that century by ten, then the population will double itself in twenty-five years; the ten will become twenty in the first twenty-five years, forty in the second, eighty in the third, one hundred and sixty in the last, while the food will only become twenty in the first, thirty in the second, forty in the third, fifty in the fourth. If this is true, it shows the tendency of population to outrun subsistence. But of course it needs to be shown from experience that, while the strength of the desire remains the same in the later stages of the growth of population as in the earlier, the laboriousness of the labour is greater in the later stages of the increase of food than in the earlier. It is the plain truth, says Malthus, that nature is niggardly in her gifts to man, and by no means keeps pace with his desires. If men would satisfy their desire of food at the old rate of speed, they must exert their mind or their body much more than at first.[[123]] An obvious objection presents itself. Since man’s food consists after all of the lower forms of life, animal and vegetable, and since these admittedly tend to increase, unchecked by themselves, in a geometrical ratio, it might be thought that the increase of human population and the increase of its food could proceed together, with equal ease. But the answer is that this unchecked geometrical increase of the first could go on only so long as there was room for it. It could only be true, for example, of wheat in the corn-field at the time when the seed of it was sown, and the field was all before it. The equality of the two ratios would only be true of the first crop.[[124]] At first there might be five or sixfold the seed; but in after years, though the geometrical increase from the seed would tend to be the same, there could be no geometrical increase of the total crop by unassisted nature. The earth has no tendency to increase its surface. There is a tendency of animals and vegetables to increase geometrically, in their quality of living things, but not in their quality of being food for man. The same amount of produce might no doubt be gained on a fresh field, from the seed yielded by the first, and at the same geometrical rate; but this assumes that there is a fresh field, and we should not then be at the proper stage to contrast the two ratios. The contrast begins to show itself as soon as the given quantity of land has grown its crop, and its animal and human population have used all its food. The question is then how any increase of the said population, if they are confined to their own supplies, is at all to be made possible; the answer is, only by greater ingenuity and greater labour in the getting of food; and, however possible this may be, it can hardly be so easy as the increase of living beings by their own act.
The degree of disparity between the two will of course depend on the degree of rapidity with which an unchecked population is supposed to double itself. Sir William Petty,[[125]] with few trustworthy statistics, had supposed ten years; Euler, with somewhat better, twelve and four-fifths; but Malthus prefers to go by the safe figures of the American colonies, which he always regarded as a crucial proof that the period was not more than twenty-five. He admits the risk of his own mathematical simile when he grants that it is more easy to determine the rate of the natural increase of population than the rate of the increase of food which is in a much less degree natural (or spontaneous); and he argues from what had been done in England in his own time that the increase would not even be in an arithmetical ratio, though agricultural improvement (thanks to Arthur Young and the Board of Agriculture, and the long reign of high prices) was raising the average produce very sensibly. If the Napoleonic times were the times of a forced population in England, they were also the times of a forced agricultural production. Yet we ourselves, long after this stimulus, and after much high farming unknown to our fathers, have reached only an average produce of twenty-eight bushels per acre of arable land as compared with twenty-three in 1770,[[126]] while the population has risen from about six millions to thirty-five. It may be said that applies only to wheat. But until lately wheat-growing was the chief object of all our scientific agriculture; and this is the result of a century’s improvements. It is far from an arithmetical increase; and, even had the produce been multiplied sevenfold, along with the population, this would not overthrow the contention of Malthus, for he is not speaking of any and every increase of food, but of such an increase made by the same methods and by the same kind of labour as raised the old supplies.[[127]] Once it is acknowledged that to raise new food requires greater labour and new inventions, while to bring new men into the world requires nothing more than in all times past, the disparity of the two is already admitted. The fact that the two processes are both dependent on the action of man, and both practically illimitable, does not prevent them from being essentially unlike.[[128]] Objectors often suppose that the tendency of population to outrun subsistence is contradicted by the existence of unpeopled or thinly-peopled countries, just as if the tendency of bodies to attract each other were contradicted by the incompressibility of matter. The important point to notice is that the one power is greater than the other. The one is to the other as the hare is to the tortoise in the fable. To make the slow tortoise win the race, we must send the hare to sleep.[[129]]
Carey (Social Science, vol. i. ch. iii. § 5) represents the view of Malthus by the following propositions:—1. “Matter tends to take upon itself higher forms,” passing from inorganic to vegetable and animal life, and from these to man. 2. Matter tends to take on itself the vegetable and animal forms in an arithmetic ratio only. 3. It tends to take its highest form, man, in a geometrical ratio, so that the highest outstrips the lowest. In short he believes that Malthus holds the geometrical increase to be true of man alone, and only the arithmetical to be true of animals and vegetables. But Malthus really attributed the tendency to geometrical increase to all life whatsoever, and arithmetical to all food, as such.
In Macvey Napier’s Supplement to the Encyclopædia Britannica (1824) Malthus has left his mature statement of his cardinal principles, and, at the risk of repetition, that account may be added here. The main difference from the essay is in arrangement of the leading ideas; and we may learn at least what he conceived to be their relative importance towards the end of his life.
He begins by observing (1) that all living things, of whatever kind, when furnished with their proper nourishment tend to increase in a geometrical ratio, whether (as wheat) by multiplying sixfold in one year, or (as sheep) by doubling their numbers in two years, tending to fill the earth, the one in fourteen, the other in seventy-six years. But (2) as a matter of fact they do not so increase, and the reason is either man’s want of will or man’s want of power to provide them their proper soil or pasture. The actual rate of increase is extremely slow, while the power of increase is prodigious. (3) Physically man is as the rest; and if we ask what is the factor of his geometrical increase, we can only tell it, as in the case of wheat and sheep, by experience. (4) In the case of other living beings, where there are most room and food there is greatest increase. These conditions are best fulfilled for man in the United States, where the distribution of wealth is better than in other equally fertile places, and the greater number share the advantages. The American census shows for the three decades between 1790 and 1820 a rate of increase that would double the numbers in 22⅓, 22½, and 23⁷⁄₁₂ years respectively, after we deduct as immigrants ten thousand on an average every year.