Only intelligence tests can answer these questions and grade the raw material with which education works. Without them we can never distinguish the results of our educational efforts with a given child from the influence of the child’s original endowment. Such tests would have told us, for example, whether the much-discussed “wonder children,” such as the Sidis and Wiener boys and the Stoner girl, owe their precocious intellectual prowess to superior training (as their parents believe) or to superior native ability. The supposed effects upon mental development of new methods of mind training, which are exploited so confidently from time to time (e.g., the Montessori method and the various systems of sensory and motor training for the feeble-minded), will have to be checked up by the same kind of scientific measurement.
In all these fields intelligence tests are certain to play an ever-increasing rôle. With the exception of moral character there is nothing as significant for a child’s future as his grade of intelligence. Even health itself is likely to have less influence in determining success in life. Although strength and swiftness have always had great survival value among the lower animals, these characteristics have long since lost their supremacy in man’s struggle for existence. For us the rule of brawn has been broken, and intelligence has become the decisive factor in success. Schools, railroads, factories, and the largest commercial concerns may be successfully managed by persons who are physically weak or even sickly. One who has intelligence constantly measures opportunities against his own strength or weakness and adjusts himself to conditions by following those leads which promise most toward the realization of his individual possibilities.
All classes of intellects, the weakest as well as the strongest, will profit by the application of their talents to tasks which are consonant with their ability. When we have learned the lessons which intelligence tests have to teach, we shall no longer blame mentally defective workmen for their industrial inefficiency, punish weak-minded children because of their inability to learn, or imprison and hang mentally defective criminals because they lacked the intelligence to appreciate the ordinary codes of social conduct.
FOOTNOTES:
[1] See [References] at end of volume.
[2] H. H. Goddard: The Kallikak Family. (1914.) 141 pp.
[3] Danielson and Davenport: The Hill Folk. Eugenics Record Office, Memoir No. 1. 1912. 56 pp.
[4] Estabrook and Davenport: The Nam Family. Eugenics Record Office Memoir No. 2. (1912). 85 pp.
[5] R. L. Dugdale: The Jukes. (Fourth edition, 1910.) 120 pp. G. P. Putnam’s Sons.