Page:Popular Science Monthly Volume 63.djvu/520

516

N the present article I propose to present for the first time, so far as I know, some figures proving a perfect correlation between mental and moral qualities. In addition, I have some data showing, not the birth rate, but what is more to the point, the number of children who have reached adult age, born to ten different groups of parents, arranged according to their moral qualities. Both series of facts taken together give us an insight into the progress of the purely intellectual faculties. They show how the mental level in each generation may be raised by no other force than natural selection.

The complete acceptance of the theory of the 'survival of the fittest' as an explanation of evolution has had for one of its greatest bugbears the disbelief that such a force could of itself be sufficient to explain improvement in the higher human traits. In the lower forms of animal life the advantages of intelligence in the struggle for existence are evident. Cunning and strength mean better sustenance or surer escape from natural enemies. But how can such brute forces as these be of determining significance among individuals of the human species, especially during the latter ages in which man has risen above barbarism? That man has evolved is admitted, that he will continue on the upward road is generally believed, but how is an unsolved problem.

For those who believe in the inheritance of acquired characteristics, the accumulated effects of education and superior outward advantages are the forces on which the present has been built and on which the future is to rely. For those who doubt or deny the old Lamarckian principles, and we believe an increasing number of naturalists belong to this school, no such easy explanation is at hand. Some writers consider that acquired characteristics are probably not directly inherited through the physiology of the hereditary mechanism, but that the accumulated culture of each generation creates a new environment which in each generation becomes the bequest handed on to the next. In this way institutions, scientific improvement and traditions go on from century to century in their work of building up the race. It is difficult to see how men really and essentially improved or superior in natural endowments could ever be produced through the working of such a process, even in an aconeon [sic] of time. And, indeed, it is denied that