We may conclude, therefore, that given anything approaching normal educational advantages, the test is really a measure of intelligence. Used with due caution, it is perhaps as valuable as any other test in the scale. It is only necessary, in case of failure, to ascertain the facts regarding the child’s educational opportunities. Even this precaution is superfluous in case the subject tests as low as 8 years by the remainder of the scale. A safe rule is to omit the test from the calculation of mental age if the subject has not attended school the equivalent of two or three years.
It has been contended by some that tests in which success depends upon language mastery cannot be real tests of intelligence. By such critics language tests have been set over against intelligence tests as contrasting opposites. It is easy to show, however, that this view is superficial and psychologically unsound. Every one who has an acquaintance with the facts of mental growth knows that language mastery of some degree is the sine qua non of conceptual thinking. Language growth, in fact, mirrors the entire mental development. There are few more reliable indications of a subject’s stage of intellectual maturity than his mastery of language.
The rate of reading, for example, is a measure of the rate of association. Letters become associated together in certain combinations making words, words into word groups and sentences. Recognition is for the most part an associative process. Rapid and accurate association will mean ready recognition of the printed form. Since language units (whether letters, words, or word groups) have more or less preferred associations according to their habitual arrangement into larger units, it comes about that in the normal mind under normal conditions these preferred sequences arouse the apperceptive complex necessary to make a running recognition rapid and easy. It is reasonable to suppose that in the subnormal mind the habitual common associations are less firmly fixed, thus diminishing the effectiveness of the ever-changing apperceptive expectancy. Reading is, therefore, largely dependent on what James calls the “fringe of consciousness” and the “consciousness of meaning.” In reading connected matter, every unit is big with a mass of tendencies. The smaller and more isolated the unit, the greater is the number of possibilities. Every added unit acts as a modifier limiting the number of tendencies, until we have finally, in case of a large mental unit, a fairly manageable whole. When the most logical and suitable of these associations arise easily from subconsciousness to consciousness, recognition is made easy, and their doing so will depend on whether the habitual relations of the elements have left permanent traces in the mind.
The reading of the subnormal subject bears a close analogy to the reading of nonsense matter by the normal person. It has been ascertained by experiment that such reading requires about twice as much time as the reading of connected matter. This is true for the reason that out of thousands of associations possible with each word, no particular association is favored. The apperceptive expectancy, practically nil in the reading of nonsense material, must be decidedly deficient in all poor reading.
Furthermore, in the case of the ordinary reader there is a feeling of rightness or wrongness about the thought sequences. That less intelligent subjects have this sense of fitness to a much less degree is evidenced by their passing over words so mutilated in pronunciation as to deprive them of all meaning. The transposition of letters and words, and the failure to observe marks of punctuation, point to the same thing. In other words, all the reading of the stupid subject is with material which to him is more or less nonsensical.[66]
A little observation will convince one that mentally retarded subjects, even when they possess a reasonable degree of fluency in recognizing printed words, do not sense shades of meaning. Their reading is by small units. Words and phrases do not fuse into one mental content, but remain relatively unconnected. The expression is monotonous and the voice has more of the unnatural “schoolroom” pitch. They read more slowly, more often misplace the emphasis, and miscall more words. In short, one who has psychological insight and is acquainted with reading standards can easily detect the symptoms of intellectual inferiority by hearing a dull subject read a brief selection.
The giving of memories is also significant. Feeble-minded adults who have been well schooled are sometimes able to read the words of the text fairly fluently, but are usually unable to give more than a scanty report of what has been read. The scope of attention has been exhausted in the mere recognition and pronouncing of words. In general, the greater the mechanical difficulties which a subject encounters, the less adequate is his report of memories.
The test has, however, one real fault. School children have a certain advantage in it over older persons of the same mental age whose school experience is less recent. Adult subjects tend to give their report in less literal form. It is necessary, therefore, to give credit for the reproduction of the ideas of the passage rather than for strictly literal “memories.”
The selection we have used is, with minor changes, the same as Binet’s. His selection was divided into nineteen memories. The one here given has twenty-one memories. Binet used the test both in year VIII and year IX, requiring two memories at year VIII and six memories at year IX. When we require eight memories, as we have done, the test becomes difficult enough for non-selected school children of 10 years. Location in year X seems preferable, because it insures that the child will almost certainly have had the schooling requisite for learning to read a selection of this difficulty, even if he has started to school at a later age than is customary. Naturally, placing the test higher in the scale makes it more a test of report and less a test of ability to recognize and pronounce printed words.