THE PROBLEM OF POPULATION 1 1. Introduction: static and dynamic problems of economics. 1 2.. A static economy. 1 3. Dynamics and the social point of view. 1 4. Rhythmic change and cumulative change. 1 5. Some forces making for change. 1 6. Population-change as a dynamic force. 1 7. The Malthu elan doctrine. 1 8. Tendency versus actuality. 1 9. Food limit versus moral restraint. 1 10. Inadequate recognition of psychic factors. 1 11. The overplus of blossom. 1 12. Limit of the food supply. i 13. Eater and eaten. 1 14. Features of the biologic stage. i 15. Primitive popu lations in the biologic stage. § 16. War and the pressure of population.
§ 1. Introduction : static and dynamic problems of eco nomics. We have now to shift our point of view from that we have held thus far and, in concluding this volume, we are to survey our subject more broadly and with a somewhat dif ferent purpose. Our study of value began with individual choice and we have followed this process of individual choice in its manifold workings in the various problems of value and price. Men in their economic affairs are never absolutely at rest either in mind or in body. (See Chapter 4, especially section 6 on changes of desires and of valuations.) Desires wax and wane every day, and each day goods for daily exist ence and gratification must be secured through the labor and wealth of the community, even in the most unchanging form of society. Each individual is seeking to find the best adjust ment for himself—a never-ending process. If for a moment (and in so far as) this is attained, there results an equilib rium for each individual, where he has no motive to change.
This process of the individual's adjustment is a part of a larger adjustment; his change goes on within a larger process of change, that of society as a whole. There is a real need, however, to distinguish in many economic problems between that play of individual motives and forces which merely re sults in maintaining a status quo, and that which transforms the whole society into, or carries it to, a different condition. The one is a static adjustment, the other a dynamic adjust ment, or process. To draw an analogy: the human body between about the ages of twenty and forty is constantly renewing itself, is the seat of ceaseless processes, yet is com paratively static, is changing only slowly. Earlier was the dynamic period of childhood's growth, and later will be that of age's decline. So an economy may through long periods show slight changes, and again, rapid changes either upward or downward in respect to any feature.
Where the whole economic situation is one of balanced forces, giving a comparatively stable adjustment of labor and wealth, and of prices, it is a static situation. And an eco nomic society where this stable condition is normal is a static § 2. A static economy. Let us form a picture of a static economy. The number of persons is unchanged from genera tion to generation. Each year the number of births is just balanced by the number of deaths. The average natural abil ity of the new born must be just equal to that of the deceased, and that this should be so, either there must be no differences whatever in the natural ability of the families, or each class and family of the population must contribute in the same ratio to the number of surviving children. The industrial education and training of each oncoming generation is the same as that of the last, and this extends to every faculty of the mind and habit of life that affects thrift, industry, and choice of goods. Minor variations in particular families might offset each other and maintain an unchanged average. The population of a static economy is in quantity and quai 1 See note on Definitions at end of chapter.
ity like a reservoir of water fed by a pipe at an even rate and having an outlet of just the same capacity, so that the level and quality remain unaltered.
In a static economy the production of goods from year to year is the same in kind, quality, and quantity. Seasonal changes within the year cause many values to move up and down, but such changes as this—each year the same and com pleting their cycle within the year—are accounted a mark of a static rather than of a dynamic economy.
The area of land as well as the kinds of resources and the ease with which they are obtained, are unchanging. This means that they are used in an absolutely durative manner. Technic is stationary; the sano kinds of tools, processes, and methods pass from father to son. Abstinence is solely of the conservative kind. Under these conditions the "normal" equilibrium of prices of commodities, labor of all sorts, uses of goods, capitalization, and rate of interest would be un changing. Not that this equilibrium is maintained in a me chanical, automatic manner, in which men have no part. These levels of values and prices can be maintained only as a result of ceaseless choices, bids, and efforts on the part of all the members of the community. Men in a static society, each seeking to make advantageous choices, are just as much active factors in maintaining a level of prices as are men in a highly dynamic state. But given the static conditions of population, culture, resources, and technic, the subjective and objective conditions combine to give a static level of values.
Such a state of human society in this absolute degree never has been known, but it has been more or less approximated in many times and places. Examples are many primitive soci eties, such as the Esquimaux, native Australians, etc., con tinuing unchanged for many centuries; ancient Egypt and medieval Europe. Until the twentieth century China, indeed the Orient generally, has been synonymous with the unchange able in social and economic conditions. "Better fifty years of Europe than a cycle of Cathay." Many features of a static society are present everywhere much of the time. This conception is a type or norm by which we can study and judge the effect of each kind of forces separately, and not as they occur in haphazard combinations.
§ 3. Dynamics and the social point of view. Heretofore our study has been purposely confined as far as possible to the static aspects of the value and price problems. We were bent upon tracing the process by which individuals adjust their funds of wealth and labor to a general economic situation or level of valuation which they find and which they must accept as a fact given. We have recognized, however, that the indi vidual finds himself compelled, again and again, to adjust his choices to a somewhat altered general situation, or in turn, may, by his action (discovery, invention, enterprise) start new forces into motion which will eventually alter the situa tion further. In the foregoing discussion of value and price, this distinction between static and dynamic forces, problems, principles, and societies has been more than implied. We have repeatedly referred to the more or less general changes as influencing the personal gains and losses of individuals, and even of whole classes of society. (See Chapter 27, section 13, note.) But in these references the purpose was still primarily to show the effects upon individual fortunes. We have now to take the larger view, and to consider these changes with reference to the effects upon the whole body of society.
Any state of economic forces may be studied in relation to value and price. If the situation were quite static, the price of every factor would be unchanging. A new cumula tive factor would carry the level up or down in the period of dynamic change. There it would remain until other forces again raised it or lowered it to a new level, permanent so far as that one force can determine it.
Dynamic problems in economics are not always easily dis tinguishable from static problems; but in most cases the dif ference is clear. Changes may range from very slight and temporary departures from a certain static equilibrium to In a completely static state the level of prices and incomes would continue unchanged throughout the successive periods of time, as repre sented by the line AAA which remains parallel with the base line. The dotted line B which oscillates above and below A represents the rhythmic change. Line C represents a transformational (truly dynamic) change through a period of time to a permanently higher static level of CC'; whereas D represents a transformational change and a lower static level DD'.
those that are relatively great and lasting. Accordingly, two types of dynamic change may be distinguished. One is the rhythmic change, the stato-dynamic change, where the move ment more or less regularly oscillates above or below a "nor mal equilibrium"; it is cyclical, in that the change runs a cycle above and below the normal and back to the starting point. This is dynamic in any brief period, but merely an unstable static when considered as a long-time average. An other type of dynamic change is cumulative, or transforma tional, or permanent, meaning that the forces at work are not such as will of themselves generate resistance (as does a swinging pendulum) sufficient to carry them back to the starting point.
§ 5. Some forces making for change. With many of these changes there is nothing that makes for permanent prog ress. There is a maximum and a minimum of prosperity, but the pendulum has a limited swing. There is in a rhythmi cally dynamic society far more of risk and uncertainty, of need and opportunity for judgment, of range for enterprise and alert management, than in a purely static state. None of these forces and influences change with perfect regularity, and even when the general average is pretty even from one cycle to the other, there is an element of the unpredictable any year about the total movement as well as about the details.
Only a few of the influences that bring about rhythmic changes are mentioned here. Political forces are constantly changing and bring economic results. In the past it has been almost proverbial that in each generation a nation must have a war, having had just time enough to recover from the last one. A vacillating policy of taxation, of foreign trade and tariff duties, and of economic legislation keeps business in a constant process of adjustment.
The discovery and production of the precious metals, gold and silver, follows always a somewhat irregular cycle. There result changes in the supply of money and in the scale of prices. The treatment of these particular questions is re served for a later volume, but some other dynamic changes will be here considered.
We shall therefore take up first the problem of popula tion, and ask what are the effects of a change in the number of people in and of itself, other things remaining equal. Then we shall consider what are the effects of changes in the objective factors, the area of land, its fertility, the discovery, use, and using up of natural resources, and the invention and increase of machinery. Finally we shall consider the sub jective factor, human nature, in its use, saving, and accumu lation of wealth.
§ 7. The Malthneian doctrine. The subject of popula tion was brought into prominence in economic discussion by the writings of Malthus? Before that some thoughtful com ments had been made here and there, but it had been gener ally assumed that the larger the population the better for the country. Malthus, an interested student of contemporary projects of social improvement, was struck by the significance of some facts of observation and of history, and arrived quickly at the conclusion that the excessive growth of population is the cause of much of the misery and poverty in the world.
2 An essay on the principle of population, as it affects the future improvement of society, by Robert Thomas Malthus, London, 1798. Second edition, 1803.
He believed also that this excessive increase would be sure to occur in a state of communism, and would alone be sufficient to wreck the ideal societies which the reformers of that period of the French Revolution were fond of picturing.
This was the general idea, but in some respects the thought was hazy and there is even yet room for discussion as to just what the Malthusian "principle of population" is. Some think it is expressed in the proportion of the opposing ratios; population has a tendency to increase in a geometrical ratio, and food in an arithmetical ratio. Thus, says Malthus, while food increases 1, 2, 3, 4, 5, 6, etc., population increases 1, 2, 4, 8, 16, 32, etc. This was the thought of Malthus: that popu lation was always "pressing upon" the means of subsistence, and keeping large numbers on the verge of want.
§ 8. Tendency versus actuality. " Tendency " of popula tion does not mean here an actual movement, for self-evidently population could not increase in such a ratio, for each individ ual mouth must have additional food. When population has reached 2 its rate must slacken, for one fourth of the total population in the next period would starve, or, distributing the food evenly, all would have to live on an even scantier diet, until pestilence, the effect of want, reduced the numbers. "Tendency" in respect to population meant latent possibility of the population reproducing and multiplying itself pro vided food increase kept pace; tendency in respect to food meant actual possibilities of the food being increased by the additional hands working on the same area of land.
Bearing in mind this ambiguity the principle may be ex pressed apart from the two ratios as follows. Popula tion has a tendency to outstrip means of subsistence, with the result of poverty, misery, and famine. Tendency here if carefully examined is seen to be a very complex idea, neither a simple force, nor an actual increase of numbers, but a com bination of the physiological maximum of birth rate, of the natural unlimited philoprogenitive impulse, and of adequate care and sustenance to rear the enormous number of children that would be born under these supposed conditions. But
there can not be food enough, hence misery and death. "Tendency" is what would happen if there were food enough, but in reality population can not increase beyond 2, the limit of the food supply. Likewise, in reality, the food can not increase beyond 2, for the increase of food from 2 to 3 is merely what would happen if twice as many hands could be put to work upon the same area, as in fact they can not be. Hence it is implied in the argument of Malthus (tho he does not clearly express it) that there is in any country a natural point of equilibrium between population and food which in the figures he has chosen as illustrations must be at 2 and 2. Evidently the food supply depends upon the stage of the arts of food production. As society changes from hunting to agri culture, from hand culture to plowing, etc., the food possible on the same area with the same labor increases, but population would quickly increase to this new equilibrium, of 3, 3, or 4, 4, etc. Population can not actually increase much beyond that point, for disease and other ills will then set in and again reduce the numbers.
Hence in Malthus' view the law of population, expressing the relation of the number of people to the actual food, is essentially rhythmically static. Population moves in cycles up to and slightly beyond the quantity of food it can produce, then is cut down by some catastrophe, and again slowly rises to the former equilibrium. Any margin, or sur plus of food production made possible by a cumulative dy namic force changes the normal static level around which population thereafter oscillates. Malthus shows by many his torical examples how again and again war, or the chance failure of crops, or pestilence has greatly reduced the popu lation of a country, and how almost invariably this loss has been made up by a rapid increase in numbers in a single generation up to the limit of the food supply, followed by another period of stationary numbers.
very unclearly expressed and doubtless very cloudy in the mind of Malthus was the nature of this limit of the food sup ply. He assumes that there is such a limit at each time and country, but nowhere carefully analyzes the idea. He vaguely implies that it is all the food that the people can get, and his principle of population usually has a materialistic, a fatalistic character, with its picture of a limited food supply predeter mined, in a way not quite clear, by forces outside of the choice and control of men, and setting the subsistence limit to the total population.
Yet in making his main argument against communism he shows that at least those families with private property do not put their whole incomes into food, but keep their numbers down, and direct toward other things than food a large part of the agents they control. This choice, or quality of mind, is recognized in the first edition of the essay and in the second edition is named moral restraint. A psychological factor enters here to take a place alongside of the materialistic fac tor, and the two never are reconciled by Malthus. Moral re straint, Malthus seems to think, is limited to a small section of the population, does not act upon the masses, and plays no appreciable part in explaining the total population of the country. He still thinks of population on the whole as regu lated by the food supply. Yet Malthus does not think it use less to advise the working classes for their own welfare to postpone marriage and thus limit the size of their families. This notion became the starting point for the propaganda called neo-Malthusianism (which has advocated proposals very different from that of Malthus) to prevent very large fain flies among the working classes.
§ 10. Inadequate recognition of psychic factors. Indeed the work of Malthus is replete with suggestions and with keen observations of history, not sufficiently analyzed or or ganized, and often expressed in ambiguous terms. The Mal thusian doctrine of population has been the center of a con tinuous, and often bitter, controversy ever since its appear ance, both as matter of economic theory and as to its bearing upon radical social reforms. Because of the features in it we have just noted it is futile now to line up for or against Malthusianism. Hardly any two persons mean just the same thing by that term. We may agree that Malthus got hold of a great biological principle without understanding its full bearings. Darwin was struck by this in reading Malthus' book, and made it the starting point of his great doctrine of natural selection in explaining evolution. Since 1859, there fore, we are in a position to see the subject in much broader perspective. It is best therefore to put aside from our thoughts prejudices and controversies clustering around the Malthusian doctrine, and to find a basis for a doctrine of pop ulation in the ideas of modern biology and psychology and in the statistical facts of our times.
§ 11. The overplus of blossom. A doctrine of population is the grouping and explanation of the various influences that combine to determine the number of people in the several localities and in the world as a whole. The most fundamental fact in the doctrine of population is the surplus of life germs. In every species of living organism, vegetable or animal, the production of germ cells in each generation is vastly greater than the number that develops into living offspring. Yet the number of offspring born is much greater, in most species vastly greater, than would suffice to maintain the number of living individuals undiminished if all the young lived to ma turity. Each species has an average or normal birth rate, great or small. Insects produce thousands of eggs each, fish produce hundreds, the rabbit a score of young in a year, and the elephant but one in three years. Clearly there is a gen eral inverse relation between the intelligent care that the parents of any species give to their offspring, and the number of life germs produced. Nature economizes the forces of the species by a gradual reduction of the real surplus, but always leaves what the engineers call a "factor of safety." There are so many chances of accident, that if the number of germs is enough only in favorable conditions, the species will become extinct under any conditions in the least unfavorable.
§ 12. Limit of the food supply. These myriads of seeds seeking for a chance to germinate, these myriads of young in every species seeking to survive, can not possibly grow to maturity. Even the slow-breeding elephant, with a period of gestation of three years, and producing one calf at a birth, would cover the entire earth and leave no standing room in a few centuries if every calf born could live to maturity. In how much briefer time would the fast-breeding animals and insects cover every foot of the earth ! The limit of the food supply alone would prevent this. This has been demonstrated repeatedly when herbivorous animals have been placed on an island from which they could not escape, and where there were no large beasts of prey. This demonstration was made on an enormous scale when the rabbit was introduced into Aus tralia, that peculiar and long isolated continent containing none of the rabbit's ancient enemies. The rabbits increased and devastated great areas, and tho they have been hunted, trapped, and poisoned by the millions, and great numbers of them have died of starvation outside the wire fences erected to stop their progress, they still continue to be a pest. If there were no other limit earlier interposed, this ultimate limit of the food supply would quickly check the increase of any form of animal life.
§ 13. Eater and eaten. The destruction of one kind of animal by another limits numbers in another way. The num ber of lions is limited by the number of their prey in the region where they roam. The number of deer, therefore, is limited in two ways, by the amount of their food and by the number of lions which catch the deer. The more numerous the lions, the fewer the deer; the fewer the deer, the greater the supply of vegetable food ; as the pressure increases one side, it decreases on the other, until an equilibrium is reached. Some carnivorous animals will in times of great hunger eat the weaker members of their own species, even their own young. The actual limitation here is thus not starvation, but violence induced by hunger.
Geology tells the story of a slow and steady change that has gone on in the earth and in the species of animals that inhabit it. History records some rapid changes due to con vulsions of nature or to interference by man with the natural conditions. But the usual condition is an equilibrium of numbers, long maintained. Tho each species of animal has a capacity for unlimited multiplication, throughout nature each keeps its customary place, changing little despite its ef forts to increase and to crowd into the habitat of other species.
§ 14. Features of the biologic stage. Every species of animals thus presents the problem of the adjustment of num bers to Among wild animals this adjustment is in the biologic or instinctive stage, which is characterized by these features: (a) A physiological factor, the physical capability of developing reproductive cells, and of nourishing and protecting them up to the time that they become separate living beings through various processes in the oviparous and viviparous animals. (b) A psychological factor, the instinct of reproduction impelling to the realization of this physio logical factor. (c) An absence of any knowledge or under standing of the relation between the instinct and the birth of offspring, and consequently the lack of any attempt to re strain or regulate the birth rate. (d) "The physiological maximum birth rate," being the number of births relative to the number of individuals capable of reproduction, that re sults from the unhindered operation of the two prime factors, physiological and psychological. (e) A certain degree of parental care after birth, normal to each species, to help the young through the early period of life. (f) The survival of the individuals thereafter depending on their inherent strength, vigor, and habits of life (including gregariousness a This is sometimes for convenience called the problem of "population," altho this is taking liberties with the derivation from popu/ua, people.
and cooperation), and on the objective conditions of accidents, disease, food supply, rivals, and enemies.
§ 15. Primitive populations in the biologic stage. The long life of the human race on this globe has been spent al most entirely in this instinctive stage of population. In many savage tribes when first visited by European travelers, the physiological maximum birth rate seems to have been nearly attained. In some tribes it was well nigh normal that a woman of forty years of age had given birth to twenty chil dren—yet those tribes had only a stationary population. Every Esquimau girl is married in her 'teens and carries a baby on her back each summer, yet the population of Esqui maux does not increase. To the simpler native peoples even to-day the nature of birth is a mystery (paragraph (c) above). A recent scientific observer of the Australian tribes found them still in this state. Every girl is married, and every widow is remarried within six weeks after the death of her husband. This is the biologic stage of population, remarkable in that with a maximum birth rate the total popu lation is either stationary or merely rhythmically changing.
Few human societies known to us are so primitive that they have not passed this stage, but many societies have risen only little above it. In most savage tribes, where starvation, dis ease, and war are constantly at work, the difficult task is to maintain the population. The birth rate is enormous, but few of those born arrive at maturity. It would be hazardous to tribal existence under these conditions to limit the birth rate. The custom of the adoption of captives from hostile tribes is wide-spread, because the efficiency—the very survival— of the tribe depends on keeping up its number of warriors.
§ 16. War and the pressure of population. War is the normal condition of most primitive tribes. Its cause usually appears to be standing feuds and ancient enmities, but the deeper and abiding economic cause is the struggle for hunt ing grounds, for pasturage, and for control of natural re sources. When resorting to war as the rude remedy for over population, mankind is hardly above the animals, who fight for food against other species of animals or against their own kind. Hunting, fishing, or pastoral people, or those in the earlier stages of agriculture, require a large area for a small population. Distant excursions and frequent forays, when food fails, develop rival claims to favored districts, and war is the only settlement. Fighting under these conditions is an activity of such economic importance that much of the energy of the tribe must be strenuously given to it. The ceaseless loss of life in savage wars is almost incredible to modern minds. The successive invasions of the Roman Empire by the Teutonic tribes, and the later inundations of medieval Europe by the fierce pastoral tribes of central Asia, were undoubtedly due to the increase of population and the outgrowing of resources by these barbarian peoples, or to the failure of their food supplies because of seasonal or of climatic changes.
Non Definitions. Statics (status, state, stationary) is that phase of a science which has to do with an equilibrium which must result in time from the existing group of forces, operating in unaltered magnitude. Dynamics (dynamic force, movement) is that phase which has to do with the changes in process as the result of new or stronger or weaker forces, which are more or less permanently unsettling the static equi librium and are carrying the point of normal equilibrium itself to higher or lower levels. The terms static and dynamic in economics, therefore, may be applied to forces, prices, equilibriums, problems, situ ations, and economies (altho the forces may meet with increasing re sistance that at length puts a limit to their effects, as the resistance of a spring balance checks the weight at a certain point). The change may be either progressive or retrogressive, and a higher or a lower level may be reached and maintained until some quite different force coming from another direction is operative. There are changes that in a brief view appear to be cumulative, which on longer study are seen to be rhythmic. Again and again men have been forced to revise their judgments, either hopeful or discouraging, of current tendencies, after time had enabled them to see a larger segment of the curve of change returning to its former level.