The proletariat constitutes a large majority of the inhabitants of the urban districts; the proportion of artificially reared children is greater than in the country, the housing conditions are less favourable, there is less opportunity for open-air life, venereal diseases are more prevalent, and fertility is lower. But against these considerations we must set the fact that the urban population is more intelligent, and for this reason better understands the various methods of artificial feeding of infants; the fact that charitable institutions are more effective in the towns, and the fact that in the towns better hygienic conditions prevail. The sanitary improvement of the towns by better cleansing of the streets, an improved water supply, better methods of disposing of sewage and refuse, &c., has led to a reduction not merely of the general urban death-rate, but also of the infantile urban death-rate; whereas in the country districts these rates have remained stationary, or have even undergone an increase. In wealthy towns the death-rate is lower than in poor towns; like differences are observed as between the rich and the poor quarters of one and the same town. Wealth has so marked an influence in lowering infant mortality that in the wealthy villa quarters of large towns the infantile death-rate may be as low as from 10 to 20 per mille.
The Effect of Housing Conditions.—The infantile death-rate is very closely connected with the character of the housing conditions. The rate of infant mortality in any particular dwelling varies directly with the number of inhabitants, and varies inversely with the number of rooms available per family. Those living in the upper stories of tenement houses have a higher death-rate than infants living in lower stories and basements. This influence of bad housing conditions in producing a rise in the infantile death-rate is only to be expected. The habitation exercises its influence upon the infant by day and by night, and through every detail of the infant’s life. To give one instance, there is an intimate connection between the quality of the dwelling and the quality of the infant’s food; in a suitable dwelling milk may be more readily kept cool, preserved from contamination, sterilised, &c.
The Effect of Age.—The degree to which bad conditions of life endanger health varies inversely with the age. The maximum danger to health from such conditions is incurred by infants. The younger the infant the greater the danger that bad conditions will prove fatal; and most of the environmental factors unfavourable to the maintenance of infant life come into operation immediately after birth. The younger the infant, the less resistant it is to external influences. Therefore the younger the infant, the more carefully does it need to be watched and safeguarded. Physicians and statisticians lay great stress upon the degree to which the infant’s chances of life depend upon its age in days and months.
Time of Birth, Seasons, and Meteorological Conditions.—Is it possible to demonstrate the existence of any connection between the time of birth and the temporal variations in the infantile death-rate? In the months in which the number of births is high, the infantile death-rate is probably also higher than at other times. This is true more especially of the very cold months, when infants cannot be taken freely into the open air; it is true also of the very hot months. It is well known that the annual curve of births exhibits two notable elevations—one in February and March, and the other in September; this depends on the fact that most conceptions take place, on the one hand, in the spring-time—that is, at the time of the general awakening of nature; and, on the other hand, in December, when nature reposes, and agricultural labours are at a standstill. But owing to the fact that the factors influencing infant mortality are so numerous and variable, it is not possible to demonstrate any definite relationship between the times of maximum births and the times of maximal infantile death-rate.
The seasons and the meteorological conditions exert an influence upon infant mortality through the intermediation of their effect upon various social conditions. The infantile death-rate is highest during the summer, the rate in the months of July, August, and September greatly exceeding that in the other months of the year. During the hot season, contaminated and decomposing milk gives rise to fatal illness on all sides. When we compare different years, we find that the height of the infantile death-rate varies directly with the heat of the summer. This influence of the hot season is exerted almost exclusively upon artificially reared infants, and especially on those in whom the technique of artificial feeding is improper. It is an established fact that the children of the well-to-do largely escape a similar fate, simply because that in their case it is possible to keep the milk artificially cool, and to prepare it more carefully in other ways.
[CHAPTER IV]
THE QUALITY OF THE POPULATION; ARTIFICIAL SELECTION (EUGENICS) AND EDUCATION
Natural Selection and Artificial Selection.—The selective method practised by Nature works by means of the procreation of millions of individuals, and by the subsequent elimination of those individuals which are imperfectly or not at all adapted to their environing conditions; that is to say, natural selection operates repressively or destructively. Artificial selection, on the other hand, aims at preventing the procreation of individuals inadequately adapted to their environment; it deliberately eliminates those elements which are useless to society, or which can be utilised by society only at excessive cost: thus artificial selection is a preventive method.
Natural selection is cruel and uneconomic. As far as the human species is concerned, natural selection is not essential to our advance towards perfection; it is even to a considerable extent superfluous. In the case of humanity, racial improvement remains possible even in the absence of a relationship between the numbers of the species and the available means of subsistence so unfavourable as to necessitate a fierce struggle for existence. In the earlier stages of human evolution, such an unfavourable relationship between the numerical strength of the species and the supply of the means of subsistence was perhaps a cause of racial advance; but to-day such a relationship would be nothing but a hindrance to progress. For the human species to-day, the significance of natural selection is historical merely; the future belongs to artificial selection. The device for humanity must be, “Not Natural Selection, but Artificial Selection—Eugenics!”