We have not found a single child who tested between 70 and 80 I Q by the Stanford revision who was able to do satisfactory school work in the grade where he belonged by chronological age. Such children are usually from two to three grades retarded by the age of 12 years. On the other hand, the child with an I Q of 120 or above is almost never found below the grade for his chronological age, and occasionally he is one or two grades above. Wherever located, his school work is so superior as to suggest strongly the desirability of extra promotions. Those who test between 96 and 105 are almost never more than one grade above or below where they belong by chronological age, and even the small displacement of one year is usually determined by illness, age of beginning school, etc.
FOOTNOTES:
[28] The clinical descriptions to be given are not complete and are designed merely to aid the examiner in understanding the significance of intelligence quotients found.
[29] In other investigations, however, we have found even brighter children from very inferior homes. See p. [117] for an example.
CHAPTER VII
RELIABILITY OF THE BINET-SIMON METHOD
General value of the method.
In a former chapter we have noted certain imperfections of the scale devised by Binet and Simon; namely, that many of the tests were not correctly located, that the choice of tests was in a few cases unsatisfactory, that the directions for giving and scoring the tests were sometimes too indefinite, and that the upper and lower ranges of the scale especially stood in need of extensions and corrections. All of these faults have been quite generally admitted. The method itself, however, after being put to the test by psychologists of all countries and of all faiths, by the skeptical as well as the friendly, has amply demonstrated its value. The agreement on this point is as complete as it is regarding the scale’s imperfections.
The following quotations from prominent psychologists who have studied the method will serve to show how it is regarded by those most entitled to an opinion:—
There can be no question about the fact that the Binet-Simon tests do not make half as frequent or half as great errors in the mental ages (of feeble-minded children) as are included in gradings based on careful, prolonged general observation by experienced observers.[30]
All of the different authors who have made these researches (with Binet’s method) are in a general way unanimous in recognizing that the principle of the scale is extremely fortunate, and all believe that it offers the basis of a most useful method for the examination of intelligence.[31]
It serves as a relatively simple and speedy method of securing, by means accessible to every one, a true insight into the average level of ability of a child between 3 and 15 years of age.[32]
That, despite the differences in race and language, despite the divergences in school organization and in methods of instruction, there should be so decided agreement in the reactions of the children—is, in my opinion, the best vindication of the principle of the tests that one could imagine, because this agreement demonstrates that the tests do actually reach and discover the general developmental conditions of intelligence (so far as these are operative in public-school children of the present cultural epoch), and not mere fragments of knowledge and attainments acquired by chance.[33]
It is without doubt the most satisfactory and accurate method of determining a child’s intelligence that we have, and so far superior to everything else which has been proposed that as yet there is nothing else to be considered.[34]