The measurement of intelligence

by Lewis M. Terman

Others quickly take advantage of such relationships and name many parts of an object before leaving it, or name a number of other objects belonging to the same class. Hat, for example, suggests cap, hood, coat, shirt, shoes, stockings, etc. Pencil suggests book, slate, paper, desk, ink, map, school-yard, teacher, etc. Responses of this type may be made up of ten or a dozen plainly distinct word groups.

Another type of response consists in naming only objects present, or words which present objects immediately suggest. It is unfortunate that this occurs, since rooms in which testing is done vary so much with respect to furnishings. The subject who chooses this method is obviously handicapped if the room is relatively bare. One way to avoid this influence is to have all subjects name the words with eyes closed, but the distraction thus caused is sometimes rather disturbing. It is perhaps best for the present to adhere to the original procedure, and to follow the rule of making tests in a room containing few furnishings in addition to the necessary table and chairs.

A fourth type of response is that including a large proportion of unusual or abstract words. This is the best of all, and is hardly ever found except with subjects who are above the 11-year intelligence level.

It goes without saying that a response need not belong entirely to any one of the above types. Most responses, in fact, are characterized by a mixture of two or three of the types, one of them perhaps being dominant.

Though not without its shortcomings, the test is interesting and valuable. Success in it does not, as one might suppose, depend solely upon the size of the vocabulary. Even 8-year-olds ordinarily know the meaning of more than 3000 words, and by 10 years the vocabulary usually exceeds 5000 words, or eighty times as many as the child is expected to name in three minutes. The main factors in success are two, (1) richness and variety of previously made associations with common words; and (2) the readiness of these associations to reinstate themselves. The young or the retarded subject fishes in the ocean of his vocabulary with a single hook, so to speak. He brings up each time only one word. The subject endowed with superior intelligence employs a net (the idea of a class, for example) and brings up a half-dozen words or more. The latter accomplishes a greater amount and with less effort; but it requires intelligence and will power to avoid wasting time with detached words.

One is again and again astonished at the poverty of associations which this test discloses with retarded subjects. For twenty or thirty seconds such children may be unable to think of a single word. It would be interesting if at such periods we could get a glimpse into the subject’s consciousness. There must be some kind of mental content, but it seems too vague to be crystallized in words. The ready association of thoughts with definite words connotes a relatively high degree of intellectual advancement. Language forms are the short-hand of thought; without facile command of language, thinking is vague, clumsy, and ineffective. Conversely, vague mental content entails language shortage.

Occasionally a child of 11- or 12-year intelligence will make a poor showing in this test. When this happens it is usually due either to excessive embarrassment or to a strange persistence in running down all the words of a given class before launching out upon a new series. Occasionally, too, an intelligent subject wastes time in thinking up a beautiful list of big or unusual words. As stated by Bobertag, success is favored by a certain amount of “intellectual nonchalance,” a willingness to ignore sense and a readiness to break away from a train of associations as soon as the “point of diminishing returns” has been reached. This doubtless explains why adults sometimes make such a surprisingly poor showing in the test. They have less “intellectual nonchalance” than children, are less willing to subordinate such considerations as completeness and logical connection to the demands of speed. Knollin’s unemployed men of 12- to 13-year intelligence succeeded no better than school children of the 10-year level.

We do not believe, however, that this fault is serious enough to warrant the elimination of the test. The fact is that in a large majority of cases the score which it yields agrees fairly closely with the result of the scale as a whole. Subjects more than a year or two below the mental age of 10 years seldom succeed. Those more than a year or two above the 10-year level seldom fail.

There is another reason why the test should be retained, it often has significance beyond that which appears in the mere number of words given. The naming of unusual and abstract words is an instance of this. An unusually large number of repetitions has symptomatic significance in the other direction. It indicates a tendency to mental stereotypy, so frequently encountered in testing the feeble-minded. The proportion of repetitions made by normal children of the 10- or 11-year intelligence level rarely exceeds 2 or 3 per cent of the total number of words named; those of older retarded children of the same level occasionally reach 6 or 8 per cent.

It is conceivable, of course, that a more satisfactory test of this general nature could be devised; such, for example, as having the subject name all the words he can of a given class (four-footed animals, things to eat, articles of household furniture, trees, birds, etc.). The main objection to this form of the test is that the performance would in all probability be more influenced by environment and formal instruction than is the case with the test of naming sixty words.