efficiency and well being. It has already diminished human suffering and will in the future enable us to conquer some of the most serious evils still existing. But our rapid conquest of nature and our increasing control of different forms of life have introduced certain new evils which instead of being self-corrective seem likely to increase unless new forces in the shape of social sciences arise to correct them.
Mention has just been made of some of the undesirable effects of medicine in counteracting the forces of natural selection. The correction of this evil will not be found in biological science alone. A thorough study of the dependent, defective and delinquent classes must be made before an adequate reform can be begun and this study is an important department of social science. Modern ideas of humanity will never be satisfied with an indiscriminate production of dependents, soon eliminated by selective forces because they can not adapt themselves to the environment, even though the vigor of the population is kept up by this method. And the sense of self preservation will not long suffer the indiscriminate production of dependents who are kept alive as burdens upon the community and are even permitted to multiply and thus lower the average vitality and efficiency of a society. The only solution consistent with modern sentiment lies in studying the causes of the evil and applying the remedy at the source, so that fewer dependents will be produced and the average vitality of the population will be raised. This will be accomplished only through the cooperation of the sciences of individual and social life. Another evil effect of the unrestrained production of wealth and of the irrational propagation of human beings has attracted still greater attention and has probably been most influential of all in stimulating the study of sociology as a general science of society. The greater control over nature made possible by the advance of the natural and biological sciences and the increased wealth resulting therefrom, has affected different parts of society very unequally. Certain persons, who, for various reasons, had an early advantage in the accumulation of wealth, have been able to retain that advantage and even to pass it on to their descendants. In some cases, advantage once obtained has become cumulative. On the other hand the descendants of those who lacked special advantage, or were hindered with positive disadvantage, suffered similar and even greater disadvantage. And in the older societies the possibility of improvement through individual effort becomes more and more difficult. The resulting divergence of classes, which may have been useful in certain stages of social progress, is now seen to be out of harmony with the present trend of development. Society suffers because such a large number lack opportunity. Forces at work in progressive societies have, it is true, been lessening this evil, but modern sentiment now demands a more rapid change. And this desire has stimulated the study