Page:American Journal of Sociology Volume 4.djvu/350

332 M. and E. X. Brother and sister. Boy high-grade idiot ; paralytic. Girl a moral imbecile. Father a congenital deaf-mute and a drunkard. Mother was a prostitute and female tramp.

Such examples might be multiplied indefinitely. They are the commonplaces of the institutions for the feeble-minded.

The cases above adduced illustrate the hereditariness of imbecility. Few who have had experience in dealing with this class of neuropathies doubt that their defects are chiefly due to that cause. The degree to which this is true has been noticed but recently and the induction is still too narrow for accurate conclusions. Enough cases, however, have been observed to show that the defects classed under this head are probably more certainly hereditary than any other traits, either mental or physical. It also seems true that those children of a feeble-minded parent who escape idiocy or imbecility will probably exhibit some other type of defectiveness, either bodily or mental, or both.

The degree of heredity is, in some cases, clouded by the effects of infantile environment or pseudo-heredity, which are often similar to those of heredity proper. For sociological, if not for physiological, purposes, it may be permitted to class as hereditary influences those exerted on the child during infancy. The contact between mother and child during nursing is only less close than it was during pregnancy, and pre-natal influences, producing traits of character resembling acquired traits of the parent, are frequently, although perhaps inaccurately, classed as hereditary influences. Data on this subject are rare. Those we have point to the conclusion that infantile environment has little to do with feeble-mindedness, which is either sporadic, caused by accident, or truly hereditary.