Page:Scientific Monthly, volume 14.djvu/43

 half thinks. It is now fairly well established that the strictly median individual of our population meets with little success in dealing with abstractions more difficult than those represented in a typical course of study for eighth grade pupils, that the large majority of high-school graduates are drawn from the best 25 per cent. of the population, and that the typical university graduate ranks in intellectual endowment well within the top 10 per cent. K is stupid only by contrast. Only occasionally does an individual of his moderate ability manage to graduate from high school or enter college. Only an exceptional combination of dogged persistence and parental encouragement or other favoring circumstances can accomplish it. But the introduction of intelligence tests is showing that the majority of colleges and universities do unknowingly enroll a few students of K's intellectual caliber. How this happens and how it may be prevented are questions with which we are not here concerned.

In what, psychologically, does K's stupidity consist? Certainly not in the ordinary sensorial, perceptual or sensorimotor processes. In visual acuity he probably equals or exceeds the average savant. In the cancellation of given letters or figures in a mass of printed matter he would rank little if at all below the average of college students. He is probably in less danger of being run over by an automobile than the average college professor. He can probably drive an automobile as skillfully as the average lawyer, doctor or minister could do with the same amount of experience. There is nothing in his intelligence that would prevent him from reaping world renown as a champion athlete. His handwriting would be a credit to a statesman. His spelling is unquestionably more accurate than the spelling we find in the letters and official reports of Colonel Washington, afterward the savior and the father of his country.

Going from these relatively simple functions to the slightly higher processes of memory, we at once find unmistakable evidence of K's mental inferiority. His memory span is only five digits, direct order, and four digits, reversed order. But we have to do not merely or chiefly with a weakness of memory for discrete impressions. He is able to recognize and pronounce almost any printed word in his spoken vocabulary, but his memory span for words making sentences resembles that of a child of eight or ten years. His "report" of glibly read passages of the newspaper type is childish in its scantiness and inaccuracy, while his report of abstract passages rises little above zero efficiency. He is sometimes able to carry out directions given orally in 15-word sentences, but he responds with only a blank stare to similar directions in 30 to 40 word sentences. So many sounds will not coalesce in his mind into a meaningful whole. Nor is this weakness confined to memory for words, for he does little better with simple geometrical designs. He