THE POPULAR SCIENCE MONTHLY
|THE PSYCHOLOGY OF MENTAL DEFICIENCY|
By BIRD T. BALDWIN, Ph.D.
UNIVERSITY OF TEXAS
Come wander with me. . .
Into regions yet untrod,
And read what is still unread
In the manuscript of God.
THIS thought, which a few generations ago was uppermost in the mind of the great Agassiz when making his geological explorations, is to-day finding one form of expression in the scientific laboratory for psychological research at Vineland, N. J., where investigations are being made on the causes and conditions of human degeneration and mental deficiency. More vigorously to-day than ever before in the history of civilization, social, educational and psychological investigations are being carried into all phases of life with its misery, happiness and usefulness. Associations for charities, children's aid societies, guilds, juvenile courts and public school authorities, are asking the psychologists and physicians what can be done with these unfortunate people, the mental defectives, who are contaminating society by their presence, absorbing the time and thought that should be devoted to normal children, and later filling the almshouses, charitable institutions and prisons with illegitimate and irresponsible offspring.
The psychologist who analyzes, classifies, describes and explains mental phenomena is beginning to work effectively on the insane, the criminal and the defective. From a psychological standpoint, the border line between dull, backward and retarded children and those mentally defective, lies in a difficult and unexplained region. The inadequate knowledge of mental capacities and the desirability of accurately expressing the relative educational values of such capacities makes the field a most fertile one for research. With others, Ayres and Gulick have been studying the "laggards of our schools" for the Russell Sage Foundation, and Witmer, a pioneer in the field, has established the Psychological Clinic for the study of the normal development of every child. What of truly subnormal and mentally deficient children?
The study of mentally defective children began in 1797 when some French soldiers found "the wild boy of Aveyron" in a forest and had him taken to Dr. Pinel, of Paris, for examination. Pinel pronounced him incurable, which caused the publication of a pamphlet three years later by Itard, "De L'education d'un Homme Sauvage." This was the first important contribution to the literature of the subject; the second