Overpopulation Theories

Theories of Population

Down to the end of the eighteenth century, very little attention was given to the relation between increase of population and increase of subsistence. Plato (De republica, V) and Aristotle (De republica, II, vi) maintained, indeed, that in a communistic society marriage and the birth of children ought to be regulated and restricted by law, lest the means of support should be insufficient for all the citizens; and in some of the city-states of ancient Greece, abortion, unnatural love, and infanticide were deliberately recommended and practised for the same general end. As a rule, however, the nations of antiquity as well as those of the medieval period regarded the indefinite increase of the population as a public good, since it multiplied the number of the country's fighting men. In the words of Frederick the Great, "the number of the population constitutes the wealth of the State". Before his time over-population had not occurred in any civilized country, or at least in had not been recognized as such. It was prevented or disguised by disease, plagues, wars, and various forms of economic hardship; by fixed and simple standards of living; and by customs which adjusted the marriage rate, and consequently the rate of reproduction, to the contemporary planes of living and supplies of food. The Mercantilists, whose opinions on economic matters were widely accepted in the sixteenth, seventeenth, and eighteenth centuries, agreed with the military statesmen that increase of population was an unqualified blessing; while the Physiocrats of the eighteenth century were less confident, some of them insisting that shortage of food was a possibility that ought to be taken into account by a nation, none of them conceived the problem as of pressing importance, or dealt with it in an extended and systematic way. Several other writers, such as Montesquieu, Hume, Steuart,Wallace, Arthur Young, and Julius Möser, who had recognized the existence and general nature of the problem, likewise failed to discuss it thoroughly. This was true even of Adam Smith. Although he noted the fact that increase of population among the poorer classes is checked by scarcity of subsistence ("Wealth of Nations", London, 1776, I, viii), he did not develop the thought or draw any practical conclusions therefrom. Writing when the great industrial inventions were just beginning to indicate an enlargement of the means of living, when the new political and economic freedom seemed to promise the release and expansion of an immense amount of productive energy, and under the influence of a philosophical theory which held that the "unseen hand" of Providence would so direct the new powers and aspirations that all classes would have abundant sustenance, Smith was an unqualified optimist. He believed that the pressure of population upon subsistence had become a thing of the past.

The first author to deal systematically with the problem was Gianmaria Ortes, a Venetian friar, in a work entitled, "Reflessioni sulla populazione per rapporto all' economia nazionale." It appeared in 1790, eight years before the first edition of Malthus's famous work. According to Nitti: "Some pages of Ortes seem quite similar to those of Malthus; he comprehended the entire question, the geometrical progression of the population, the arithmetical progression of the means of subsistence, the preventive action of man, and the repressive action of nature" (Population and the Social System, p. 8). However, his book lacked the confident tone and the statistical arguments of Malthus; consequently it was soon overshadowed by the latter's production, and the Anglican divine instead of the Venetian friar became the sponsor of the world's best-known and most pessimistic theory of population.

THE THEORY OF MALTHUS

In the twenty-two years that had intervened between the appearance of Adam Smith's "Wealth of Nations" and the "Essay on the Principle of Population" (London, 1798) of the Rev. Thomas Malthus (1766-1834), the French Revolution had caused the downfall of the old social system, without improving the condition of the French people; a succession of bad harvests had impoverished the agricultural districts of England, while her credit had become so impaired by the recent wars as to render very difficult the importation of supplies from abroad. On the other hand, the rapid development of the textile and other industries through the recent mechanical inventions had called new towns into existence, and greatly stimulated the increase of population; the system of public allowances of money to all pauper children encouraged improvident marriages among the poorer classes. Although there had been a considerable increase in the national wealth as a whole, the working classes had received none of the benefit. Increased production seemed to mean a disproportionate increase in population, and a decrease in the subsistence of the poor. The obvious objection, that this condition was attributable to bad distribution rather than to insufficient production, had indeed come to the attention of Malthus. In some degree his book was an answer to that very objection. William Godwin, a disciple of the French revolutionary philosophers, chiefly in his work "Political Justice", had been defending the theory that all the evils of society arose from defective social institutions, and that there was more than enough wealth for all, if it were only distributed equally. Malthus replied to this position with his "Essay on the Principle of Population". His thesis was that population constantly tends to outrun subsistence, but that it is held in check by vice===abortion, infanticide, prostitution, and by misery in the form of war, plague, famine, and unnecessary disease. If all persons were provided with sufficient sustenance, and these checks removed, the relief would be only temporary; for the increase of marriages and births would soon produce a population far in excess of the food supply.

The first edition of Malthus's work had, therefore, a definite polemical purpose, the refutation of a communistic scheme of society. Its arguments were general and popular rather than systematic or scientific. They were based upon facts easily observed, and upon what the average man would expect to happen if vice and misery ceased to operate as checks to population. As a popular refutation of the theories of Godwin, the book was a success, but its author soon began a deeper inquiry into the facts from which he had drawn his conclusions. The result of his labours was the appearance in 1803 of a second edition of the "Essay", which differed so much in size and content from the first as to constitute, in the words of Malthus himself, "a new work". In the first chapter of the new edition he declared that "the constant tendency of all animated life to increase beyond the nourishment prepared for it" (p. 2) had not hitherto received sufficient attention. Before attempting to prove the existence of this tendency, he inquired what would be "the natural increase of population if left to exert itself in perfect freedom...under the most favourable circumstances of human industry" (p. 4). On the basis of the history of North America during the century and a half preceding 1800, and from the opinions of some economists, he concluded that "population when unchecked goes on doubling itself every 25 years, or increases in a geometrical ratio" (p. 6). A brief examination of the possibilities of food increase convinced him that this could never be "faster than in an arithmetical ratio" (p. 10). Applying these conclusions to England with its 11,000,000 inhabitants in 1800, he found that the natural result at the end of the nineteenth century would be a population of 176,000,000, and subsistence for only 55,000,000 (ibid.). The remainder of the first volume is occupied with an account of the positive checks, that is, vice and misery, which had hitherto concealed this disastrous discrepancy between population and subsistence in the various countries of the world. In the second volume he discusses the means which have been proposed to prevent an undue increase of population, and, therefore, to render unnecessary the action of the positive checks. Some of the means that he recommended were abstention from public provision for the encouragement of population increase and for the relief of the poor, and abolition of existing laws of this kind, especially the Poor Law of England. But his chief recommendation was the practice of what he called "moral restraint". That is, persons who were unable to maintain a family properly should live in chaste celibacy until such time as they had overcome this economic disability (bk. IV, passim). In the new edition of his work, consequently, Malthus not merely pointed out a new check to population, but advocated it, in order to prevent and forestall the operation of the cruel and immoral checks automatically set in motion by vice and misery.

Criticism of the Malthusian Theory

The theory may be briefly characterized thus: In its most extreme and abstract form it is false; in its more moderate form it never has been and never can be demonstrated; even if true, it is so hypothetical, and subject to so many disturbing factors, that it is of no practical value or importance. It is, of course, abstractly or theoretically possible that population may exceed subsistence, either temporarily and locally, or permanently and universally. This possibility has been frequently realized among savage peoples, and occasionally among civilized peoples, as in the case of famine. But the theory of Malthus implies something more than an abstract possibility or a temporary and local actuality. It asserts that population shows a constant tendency to outrun the food supply, a tendency, therefore, that is always about to pass into a reality if it is not counteracted. In all the six editions of his work that appeared during Malthus's lifetime, this tendency is described in the formula that population tends to increase in geometrical progression, as, 2, 4, 8, etc., while the utmost increase in subsistence that can be expected is according to an arithmetical ratio, as, 2, 3, 4, etc. So far as we know, population has never increased in geometrical ratio through any considerable period; but we cannot show that such an increase, by natural means, is physiologically impossible. All that it implies is that every married couple should have on the average four children, who would themselves marry and have the same number of children to each couple, and that this ratio should be kept up indefinitely. It is not, however, true that the means of living can be increased only in an arithmetical ratio. During the nineteenth century this ratio was considerably exceeded in many countries (cf. Wells, "Recent Economic Changes"). Malthus's view on this point was based upon a rather limited knowledge of what had been happening before his time. He did not foresee the great improvements in production and transportation which, a few years later, so greatly augmented the means of subsistence in every civilized country. In other words he compared the potential fecundity of man, the limits of which were fairly well known, with the potential fertility of the earth and the potential achievements of human invention, neither of which was known even approximately. This was a bad method, and its outcome in the hands of Malthus was a false theory.

Even if we discard the mathematical formulation of the theory, and examine it in its more moderate form, as merely asserting that population tends to outrun subsistence, we find that the theory cannot be proved. The facts adduced by Malthus in support of his contention related to the insufficiency of the food supply in many countries at many different times. Now it is true that barbarous peoples and peoples dependent upon fishing and hunting for a living have frequently lacked subsistence, especially when they were unable or unwilling to emigrate; but such has not often been the case for any considerable time among civilized nations. Want of food among the latter has usually been due to a bad industrial organization and a bad distribution, rather than to the poverty of nature, or the unproductiveness of man. Even today a large proportion of the inhabitants of every country is insufficiently nourished, but no intelligent person attributes this condition to an absolute excess of population over subsistence or productiveness. Since Malthus did not give sufficient attention to the evils of distribution, he failed to prove that his theory was generally true, even of the time before he wrote; since he did not suspect the great improvements in production that were soon to take place, he was still less able to show that it would be universally valid. While admitting the weakness of his argument, some of his later followers insist that the theory is true in a general way. Population, if unchecked by a prudential regulation of marriages and births, can and in all probability often will outrun subsistence, owing to the law of diminishing returns (cf. Hadley, "Economics").

Although Malthus seems to have had some knowledge of this law, he did not use it as the basis of his conclusions. Now the "law of diminishing returns" is simply the phrase by which economists describe the well-known fact that a man cannot go on indefinitely increasing the amount of capital and labour that he expends upon a piece of land, and continue to get profitable returns. Sooner or later a point is reached where the product of the latest increment of expenditure is less than the expenditure itself. This point has already been reached in many regions, whence a part of the population is compelled to move to other land. When it has been reached everywhere, population will universally exceed subsistence. Stated in this form, Malthusianism seems to be irrefutable. Nevertheless the law of diminishing returns, like all economic laws, is true only in certain conditions. Change the conditions, in this case, the methods of production, and the law is no longer operative. With new productive processes, further expenditures of labour and capital become profitable, and the point of diminishing returns is moved farther away. This fact has received frequent illustration in the history of agriculture and mining. While it is true that new methods are not always discovered as soon as they are needed, and that men often find it more profitable to expend their additional resources upon new lands than upon the old, it is also true that we can set no definite limits to the inventive power of man, nor to the potential fertility of nature. Absolutely speaking, no one is warranted in asserting that these two forces will not be able to modify indefinitely the conditions in which the law of diminishing returns operates, so that subsistence will keep pace with population as long as men have standing room upon the earth. On the other hand, we cannot prove that if population were to increase up to the full limit of its physiological possibilities, it would always be sufficiently provided for by the fertility of nature and the inventiveness of man. We are dealing here with three unknown quantities. Upon such a basis it is impossible either to establish a social law, or conclusively to refute any particular generalization that may be set up. In the third place, the Malthusian theory, even if true, is of no practical use. The assurance that population, if unchecked, will inevitably press upon subsistence does not terrify us, when we realize that it always has been checked, by celibacy, late marriages, war, natural calamities, and other forces which are not due to scarcity of subsistence. The practical question for any people is whether these non-scarcity checks are likely to keep population within the limits of that people's productive resources. So far as the nations of the Western world are concerned, this question may be answered in the affirmative.

The use of preventive checks, such as postponement of marriage, abortion, and artificial sterility have become so common that the birth-rate has almost everywhere decreased within the last half-century, and there is no indication of a reaction in the near future. During the same period the rate of food production has considerably increased. Moreover, the decline in the birth-rate has been most pronounced among those classes whose subsistence is most ample, thus suggesting the probability that it will become equally prevalent among the poorer classes as soon as their plane of living is raised. The contingency that men may some day become so careless of the higher standards of comfort as to give up the present methods of restriction is too remote to justify anxiety on the part of this generation. Let us assume, however, that, under the influence of religion and moral teaching, all the immoral preventives of population were discarded. Even so, we have no reason to doubt that the lawful checks, such as virtuous celibacy both temporary and permanent, and the decrease of fecundity that seems to be a necessary incident of modern life, particularly in cities, would be sufficient to keep the world's inhabitants well within the bounds of its productive powers. So far as we can see at present, the Malthusian theory, even if true in the abstract and hypothetically, is so hypothetical, assumes the absence of so many factors which are always likely to be present, that it is not deserving of serious attention, except as a means of intellectual exercise. As a law of population, it is about as valuable as many of the other laws handed down by the classical economists. It is about as remote from reality as the "economic man".

And yet, this theory met with immediate and almost universal acceptance. The book in which it was expounded went through six editions while Malthus was living, and exerted a remarkable influence upon economics, sociology, and legislation during the first half of the nineteenth century. Aside from a section of the Socialists, the most important group of writers rejecting the Malthusian theory have been Catholic economists, such as Liberatore, Devas, Pesch, Antoine (cf. Pesch, "Lehrbuch der Nationalökonomie", II, 598). Being pessimistic and individualistic, the teaching of Malthus agreed thoroughly with the temper and ideas of his time. Distress was deep and general, and the political and economic theories of the day favoured the policy of laissez faire. To him perhaps more than to any other writer is due the evil repute of the orthodox economists, as opponents of legislation in the interests of the poorer classes. In the words of Devas, "Malthusianism in practice has been a grave discouragement to all works of social reform and humane legislation, which appeared as foolish sentiment defeating its kind aims by encouraging population" (Political Economy, 2nd ed., p. 198). Malthus declared that the poor created their own poverty by marrying improvidently, and that any general system of poor relief only increased and prolonged the root evil, overpopulation, from which they suffered (Essay bk. IV, passim). Although he had a genuine sympathy for the poor, and believed that the practice of "moral restraint" in postponing or foregoing marriage was the one means of bettering their condition permanently, his teaching received the cordial approbation of the wealthier classes, because it tended to relieve them of "responsibility for the condition of the working classes, by showing that the latter had chiefly themselves to blame, and not either the negligence of their superiors or the institutions of the country" (Ingram, "History of Political Economy", p. 121). His more recent followers among the economists realize that an improvement in the condition of the masses is apt to encourage a lower birth-rate, consequently they are not opposed to all measures for improvement by legislation. Many of them, however, have exaggerated the social and moral benefits of a low birth-rate, and have implicitly approved the immoral and destructive practices upon which it depends. The irony of the situation is that preventive checks, moral and immoral, have been adopted for the most part by the rich and comfortable classes, who, in the opinion of Malthus, were not called upon to make any personal contribution to the limitation of population.

The most notable results of the work and teaching of Malthus may be summed up as follows: he contributed absolutely nothing of value to human knowledge or welfare. The facts which he described and the remedies which he proposed had long been sufficiently obvious and sufficiently known. While he emphasized and in a striking way drew attention to the possibility of general overpopulation he greatly exaggerated it, and thus misled and misdirected public opinion. Had he been better informed, and seen the facts of population in their true relations, he would have realized that the proper remedies were to be sought in better social and industrial arrangements, a better distribution of wealth, and improved moral and religious education. As things have happened, his teaching has directly or indirectly led to a vast amount of social error, negligence, suffering, and immorality.

Neo-Malthusianism

In a sense this system is the extreme logical outcome of Malthusianism proper. While Malthus would have turned in horror from the practices of the newer theory, his own recommendations were much less effective as a means to the common end of both systems. The Neo-Malthusians realize better than he did, that if population is to be deliberately restricted to the desired extent, other methods than chaste abstention from or postponement of marriage are necessary. Hence they urge married couples to use artificial and immoral devices for preventing conception. Some of the most prominent leaders of this movement were Robert Dale Owen, John Stuart Mill, Charles Bradlaugh, and Annie Besant. With them deserve to be associated many economists and sociologists who implicitly advocate the same practices, inasmuch as they glorify an indefinitely expanding standard of comfort, and urge limitation of offspring as the one certain means whereby the labour of the poorest paid workers may be made scarce and dear. Some of the Neo-Malthusian leaders in England maintained that they were merely recommending to the poor what the rich denounced but secretly practiced.

In common with the older theory from which it derives its name, Neo-Malthusianism assumes that population if unchecked will exceed subsistence, but by subsistence it means a liberal, or even a progressively rising, standard of comfort. In all probability this contention is correct, at least, in the latter form; for all the indications are against the supposition that the earth can furnish an indefinitely rising standard of comfort for a population that continues to increase up to the full measure of its physiological capacity. On the other hand, the practices and the consequences of the system are far more futile, deceptive, and disastrous than those of Malthusianism. The practices are intrinsically immoral, implying as they do either foeticide, or the perversion of natural faculties and functions, to say nothing of their injurious effect upon physical health. The condition aimed at, namely, the small family or no children at all, fosters a degree of egotism and enervating self-indulgence which lessens very considerably the capacity for social service, altruism, and every form of industrial and intellectual achievement. Hence the economists, sociologists, and physicians of France condemn the low birth-rate and the small family as a grave national and social evil. On the industrial side, Neo-Malthusianism soon defeats its own end; for increased selfishness and decreased stimulus to labour are naturally followed by a smaller output of product. If the restriction of offspring were confined to the poorer classes, their labour would indeed become scarce relatively to the higher kinds of labour, and their wages would rise, provided that their productivity were not diminished through deterioration of character. As a fact, however, the comfortable classes adopt the method much more generally than do the poor, with the result that the excessive supply of unskilled labour is increased rather than diminished. Where all classes are addicted to the practice, the oversupply of unskilled labour remains relatively unchanged. The wages of all classes in France are lower than in Germany, England, or the United States (cf. Fifteenth Annual Report of the Commissioner of Labour). Finally, a constantly rising standard of comfort secured by the practices and in the moral atmosphere of Neo-Malthusianism means not a higher but a lower plane of life; not more genuine culture or loftier morals, but more abundant physical enjoyments and a more refined materialism.

OTHER THEORIES OF POPULATION

Rodbertus, Marx, Engels, Bebel, and possibly a majority of the Socialists who have considered the problem, either deny a general tendency to excessive population, or maintain that it is realized only in capitalistic society. Under Socialism there would be ample sustenance for the greatest possible increase in population, or, at any rate, for whatever increase that form of society would decide to have. Now it is quite unlikely that a Socialistic organization of production, with its lessened incentives to inventive and productive energy, would be able to provide means of living adequate to the full capacity of human fecundity; and a universally and continuously rising standard of comfort would be subject to all the physical, moral, and intellectual hindrances and consequences which beset the suicidal system of Neo-Malthusianism.

A respectable minority of economists (in this connection frequently known as "optimists") have rejected the Malthusian theory from the beginning. Among the most prominent are, Bastiat in France, List (1789-1846) in Germany, and Henry C. Carey in America. In a general way they all maintained that in proper social and industrial arrangements population will never exceed subsistence. This was likewise the position of Henry George, whose attack upon the theory of Malthus is probably more familiar to Americans than that of any other writer (cf. Progress and Poverty). Carey, whose father, Matthew Carey, the Philadelphia publisher, was a Catholic, based his view partly upon his belief in Providence, and partly upon the assumption that in every country the richest lands and land powers remain undeveloped longest; List pointed out that thickly-populated lands are frequently more prosperous than those with relatively few inhabitants, and that we have no good reason to set limits to the capacity of the earth, which could undoubtedly support many times its present population; and Bastiat, who had already observed the artificial restriction of the birth-rate in his own country, seems to have concluded that the same thing would happen in other countries whenever subsistence tended to fall below the existing standards of living. Although there is some exaggeration and uncertainty in all these positions, they are undoubtedly nearer the truth than the assumptions of Malthus.

What may be called the evolutionist theory of population was originated and incompletely stated by Charles Darwin, and developed by Herbert Spencer. In the latter form it has been adopted substantially by many biologists and sociologists. Although it was a chance reading of Malthus's work that suggested to Darwin the idea of the struggle for existence, the Spencerian theory of population is on the whole opposed to the Malthusian. According to Spencer, the process of natural selection, which involves the destruction of a large proportion of the lower organisms, increases individuality and decreases fecundity in the more developed species, especially in man. At length, population becomes automatically adjusted to subsistence at that level which is consonant with the highest progress. With regard to the future, this theory is extremely optimistic, but it is not more probable or any more capable of proof than his prophecy concerning the future identification of egoism and altruism.

On the basis of painstaking research and abundant statistics, M. Arsène Dumont concluded that Malthusianism is theoretically false and practically worthless, and that the only valuable generalizations about the relation of population to subsistence are those which concern a particular country, epoch, civilization, or form of society (cf. Nitti, op. cit.). In a democratic society, he says, the real danger is excessive limitation of the birth-rate by all classes, even the lowest. When privileged classes and social stratifications have disappeared, the members of every class strive to raise themselves above their present condition by restricting the number of their offspring. So far as it goes, this theory is a correct explanation of certain existing tendencies, but, as Father Pesch observes in reply to P. Leroy-Beaulieu, the true remedy for the French conditions is not monarchy but the Christian religion and moral teaching (op. cit., II, 639).

The theory of Nitti has a considerable similarity to that of Spencer, but the Italian sociologist expects the deliberate action of man, rather than any decrease in human fecundity, to conform population to subsistence in any society in which wealth is justly distributed, individuality strongly developed, and individual activity maintained at a high level of efficiency (op. cit.). He repudiates, however, the egotistic and socially demoralizing "prudence" which is so generally practised today for the limitation of the size of families. Nevertheless, it is utterly unlikely that the sane regulation which he desires will be obtained without the active and universal influence of religion. With this condition added, his theory seems to be the most reasonable of all those considered in this article, and does not greatly differ from that of the Catholic economists.

The latter, as we have already noted, reject the Malthusian theory and the interpretation of social facts upon which it is founded. Taking as typical the views of Devas in England, Antoine in France, Perin in Belgium, Liberatore in Italy, and Pesch in Germany (see works cited below) we may describe their views in the following terms. Where production is effectively organized, and wealth justly distributed; where the morals of the people render them industrious, frugal, averse to debilitating comforts, and willing to refrain from all immoral practices in the conjugal relation; where a considerable proportion of the people embrace the condition of religious celibacy, others live chastely and yet defer marriage for a longer or shorter period, and many emigrate whenever the population of any region becomes congested===undue pressure of population upon subsistence will never occur except locally and temporarily. Probably this is as comprehensive, and at the same time as correct a generalization as can be formulated. It may be reduced to the summary statement of Father Pesch: "Where the quality of a people is safeguarded, there need be no fear for its quantity" (op. cit., II, 624). Take care of the quality, says the learned Jesuit, and the quantity will take care of itself. Be anxious about the quantity, say the Malthusians and all the advocates of the small family, lest the quality deteriorate. It is less than eighty years since Malthus died, and a considerably shorter time has elapsed since the restriction of births became in any sense general; yet the number is rapidly increasing everywhere of thoughtful men who see that the Western world is confronted by "a problem not of excessive fecundity, but of race suicide" (Seligman, "Principles of Economics", 65).

MALTHUS, An Essay on the Principle of Population (London, 1826); NITTI, Population and the Social System (tr. London, 1894); INGRAM, A History of Political Economy (New York, 1894); DEVAS, Political Economy (London, 1901); HADLEY, Economics (New York, 1898); SELIGMAN, Principles of Economics (New York, 1905); LIBERATORE, Principles of Political Economy (tr. London, 1891); ANTOINE, Cours d'économie sociale (Paris, 1899); PERIN, Premiers principes d'économie politique (Paris, 1896); PESCH, Lehrbuch der Nationalökonomie (Freiburg, 1909); FAHLBECK, Neomalthusianismus in Zeitschrift für Sozialwissenschaft, VI (1903).

JOHN A. RYAN