Figure C 18 corresponds, with figure C 17, except that not only the parents are reckoned but the nearest defective relative in any degree.
Figure C 19 teaches that the reckoning of all the taints in the ancestry taken together with the collaterals fails to give as clear and convincing a picture of the dissimilarity in the heredity of mentally sound and diseased, as the reckoning of the taints among the parents alone. The establishment of the hereditary taint in the direct ancestry appears therefore by far the more important.
In Figure 144 (Journal f. Psychologie und Neurologie. XIII. Bd.) Drf. Hans W. Mayer gives a number of examples of heredity among moral imbeciles, and he draws the following conclusions: "Consequently moral defect in frequent combination with alcoholism is hereditary in the highest degree. Remedy: Incarceration of these dangerous individuals, not according to the accidental form of the crime committed, but as diseased and forming a public danger. If there is a risk of escape or if liberty is conceded—undoubtedly sterilization to prevent perpetuation of the defect." This latter course is already followed in North America, and a start has been made with it in Switzerland, at least in cases where the consent of the patients is obtained.
The pedigree of the family of Zero von Jorger, figure C 21 (Archiv für Rassen & Gesellschafts biologie I.), shows in a convincing manner how very important for the protection of society is the prevention of the reproduction of the degenerate. In the course of time this family has burdened the sound and fit with taxation amounting to hundreds of thousands of pounds. The author remarks: "The family Zero springs from good peasant stock intermarrying with homeless female tramps. Its history shows how alcohol (especially spirits) and bad environment (in this case always combined) may create a scourge to society which continues from generation to generation. The family has produced many criminals, lunatics and feeble-minded persons. The offspring of these are destined to die out. Their great fertility at times is counteracted by great infant mortality."
"In places regeneration is evident which invariably is inaugurated by marriage with a good woman and the consequent abandonment of the abuse of alcohol. As with the degeneration so with the regeneration the wife takes the leading part."
The question whether modern civilized races are degenerate in body and mind is much disputed. In some respects for instance in the increase of myopia and caries of the teeth it is generally admitted, but in others it is doubtful, though it may be considered an established fact that the general average of health among all civilized nations is unsatisfactory. We do not know for certain whether the general level of all or certain qualities is being lowered or not, and still less can we say what part is played by heredity.