tremendous import. The much smaller proportion of women married in the age classes 15 to 20 and 20 to 25 in England than in India largely accounts for the difference between the birth rates in the two countries. Third, in one way and another the birth rate is to an increasing extent consciously controlled in every progressive country. Fourth, early marriages and large families have become less consistent with prudence. The expense necessary to rear children to the age of self-support has become more burdensome. Besides, the rise of other ambitions in life render both sexes more cautious about assuming the marriage relation. No theory that leaves prudential considerations out of the account can possibly explain the manner in which the social and economic changes of recent years have influenced the birth rate. Our conclusion, therefore, is that the diminishing birth rate is primarily volitional, and that the various factors which make for involuntary sterility are of minor importance.
It is of interest to note that so well known a biologist as Professor H. W. Conn, of Wesleyan University, subscribes to this conclusion. He writes as follows:
- The frequency with which economists discuss the subject of population as compared with biologists deserves a passing notice. Ever since the essay of Malthus there have been few treatises upon economics without a chapter upon the subject. Certainly, any text-book which failed to consider the matter to-day would be regarded as incomplete. A century of criticism has established a fairly consistent and satisfactory body of opinion. Moreover, the periodical literature devoted to economics has in recent years been enriched by numerous articles upon the diminishing birth rate. The American Economic and Sociological Associations have now and then discussed the subject at their annual meetings. On the other hand, there is a scarcity of literature from the biological standpoint, I do not know of any place in print where a biologist has attempted to advance a definite and complete theory of population, and in arriving at the biological explanation of the diminishing birth rate I have been dependent upon stray hints found here and there and especially upon information gained by conversation with two of my colleagues, one a zoologist and the other a botanist. There is no body of doctrine upon population to which biologists subscribe at all comparable to that among economists. In other words, the weight of well-defined opinion supports the view that the decline of the birth rate is volitional.