3.Malthus' reasoning consists of three parts, which must be kept distinct.The first relates to the supply of labour.By a careful study of facts he proves that every people, of whose history we have a trustworthy record, has been so prolific that the growth of its numbers would have been rapid and continuous if it had not been checked either by a scarcity of the necessaries of life, or some other cause, that is, by disease, by war, by infanticide, or lastly by voluntary restraint.
His second position relates to the demand for labour.Like the first it is supported by facts, but by a different set of facts.He shows that up to the time at which he wrote no country (as distinguished from a city, such as Rome or Venice) had been able to obtain an abundant supply of the necessaries of life after its territory had become very thickly peopled.The produce which Nature returns to the work of man is her effective demand for population: and he shows that up to this time a rapid increase in population when already thick had not led to a proportionate increase in this demand.(13*)Thirdly, he draws the conclusion that what had been in the past, was likely to be in the future; and that the growth of population would be checked by poverty or some other cause of suffering unless it were checked by voluntary restraint.He therefore urges people to use this restraint, and, while leading lives of moral purity, to abstain from very early marriages.(14*)His position with regard to the supply of population, with which alone we are directly concerned in this chapter, remains substantially valid.The changes which the course of events has introduced into the doctrine of population relate chiefly to the second and third steps of his reasoning.We have already noticed that the English economists of the earlier half of last century overrated the tendency of an increasing population to press upon the means of subsistence; and it was not Malthus' fault that he could not foresee the great developments of steam transport by land and by sea, which have enabled Englishmen of the present generation to obtain the products of the richest lands of the earth at comparatively small cost.
But the fact that he did not foresee these changes makes the second and third steps of his argument antiquated in form; though they are still in a great measure valid in substance.It remains true that unless the checks on the growth of population in force at the end of the nineteenth century are on the whole increased (they are certain to change their form in places that are as yet imperfectly civilized) it will be impossible for the habits of comfort prevailing in Western Europe to spread themselves over the whole world and maintain themselves for many hundred years.
But of this more hereafter.(15*)
4.The growth in numbers of a people depends firstly on the Natural Increase, that is, the excess of their births over their deaths; and secondly on migration.
The number of births depends chiefly on habits relating to marriage, the early history of which is full of instruction; but we must confine ourselves here to the conditions of marriage in modern civilized countries.
The age of marriage varies with the climate.In warm climates where childbearing begins early, it ends early, in colder climates it begins later and ends later;(16*) but in every case the longer marriages are postponed beyond the age that is natural to the country, the smaller is the birth-rate; the age of the wife being of course much more important in this respect than that of the husband.(17*) Given the climate, the average age of marriage depends chiefly on the ease with which young people can establish themselves, and support a family according to the standard of comfort that prevails among their friends and acquaintances; and therefore it is different in different stations of life.
In the middle classes a man's income seldom reaches its maximum till he is forty or fifty years old; and the expense of bringing up his children is heavy and lasts for many years.The artisan earns nearly as much at twenty-one as he ever does, unless he rises to a responsible post, but he does not earn much before he is twenty-one: his children are likely to be a considerable expense to him till about the age of fifteen; unless they are sent into a factory, where they may pay their way at a very early age; and lastly the labourer earns nearly full wages at eighteen, while his children begin to pay their own expenses very early.In consequence, the average age at marriage is highest among the middle classes: it is low among the artisans and lower still among the unskilled labourers.(18*)Unskilled labourers, when not so poor as to suffer actual want and not restrained by any external cause, have seldom, if ever, shown a lower power of increase than that of doubling in thirty years; that is, of multiplying a million-fold in six hundred years, a billion-fold in twelve hundred: and hence it might be inferred a priori that their increase has never gone on without restraint for any considerable time.This inference is confirmed by the teaching of all history.Throughout Europe during the Middle Ages, and in some parts of it even up to the present time, unmarried labourers have usually slept in the farmhouse or with their parents; while a married pair have generally required a house for themselves: when a village has as many hands as it can well employ, the number of houses is not increased, and young people have to wait as best they can.