The Measurement of Intelligence Part 3

Some suggested asking the pupil such questions as the following:--

"Why do you love your parents?" "If it takes three persons seven hours to do a piece of work, would it take seven persons any longer?" "Which would you rather have, a fourth of a pie, or a half of a half?" "Which is heavier, a pound of feathers or a pound of lead?" "If you had twenty cents what would you do with it?"

A great many based their judgment mainly on the general appearance of the face and eyes. An "active" or "pa.s.sive" expression of the eyes was looked upon as especially significant. One teacher thought that a mere "glance of the eye" was sufficient to display the grade of intelligence.

If the eyes are penetrating, reflective, or show curiosity, the child must be intelligent; if they are heavy and expressionless, he must be dull. The mobility of countenance came in for frequent mention, also the shape of the head.

No one will deny that intelligence displays itself to a greater or less extent in the features; but how, asks Binet, are we going to _standardize_ a "glance of the eye" or an "expression of curiosity" so that it will serve as an exact measure of intelligence?

The fact is, the more one sees of feeble-minded children, the less reliance one comes to place upon facial expression as a sign of intelligence. Some children who are only slightly backward have the general appearance of low-grade imbeciles. On the other hand, not a few who are distinctly feeble-minded are pretty and attractive. With many such children a ready smile takes the place of comprehension. If the smile is rather sweet and sympathetic, as is often the case, the observer is almost sure to be deceived.

As regards the shape of the head, peculiar conformation of the ears, and other "stigmata," science long ago demonstrated that these are ordinarily of little or no significance.

In reply to the second question, some teachers stated that they never made a mistake, while others admitted failure in one case out of three.

Still others said, "Once in ten years," "once in twenty years," "once in a thousand times," etc.

As Binet remarks, the answers to this question are not very enlightening.

In the first place, the teacher as a rule loses sight of the pupil when he has pa.s.sed from her care, and seldom has opportunity of finding out whether his later success belies her judgment or confirms it. Errors go undiscovered for the simple reason that there is no opportunity to check them up. In the second place, her estimate is so rough that an error must be very great in order to have any meaning. If I say that a man is six feet and two inches tall, it is easy enough to apply a measuring stick and prove the correctness or incorrectness of my a.s.sertion. But if I say simply that the man is "rather tall," or "very tall," the error must be very extreme before we can expose it, particularly since the estimate can itself be checked up only by observation and not by controlled experiment.

The teachers' answers seem to justify three conclusions:--

1. Teachers do not have a very definite idea of what const.i.tutes intelligence. They tend to confuse it variously with capacity for memorizing, facility in reading, ability to master arithmetic, etc. On the whole, their standard is too academic. They fail to appreciate the one-sidedness of the school's demands upon intelligence.

In a quaintly humorous pa.s.sage discussing this tendency, Binet characterizes the child in a cla.s.s as _denature_, a French word which we may translate (though rather too literally) as "denatured." Too often this "denatured" child of the cla.s.sroom is the only child the teacher knows.

2. In judging intelligence teachers are too easily deceived by a sprightly att.i.tude, a sympathetic expression, a glance of the eye, or a chance "b.u.mp" on the head.

3. Although a few teachers seem to realize the many possibilities of error, the majority show rather undue confidence in the accuracy of their judgment.

BINET'S EXPERIMENT ON HOW TEACHERS TEST INTELLIGENCE.[9] Finally, Binet had three teachers come to his laboratory to judge the intelligence of children whom they had never seen before. Each spent an afternoon in the laboratory and examined five pupils. In each case the teacher was left free to arrive at a conclusion in her own way. Binet, who remained in the room and took notes, recounts with playful humor how the teachers were unavoidably compelled to resort to the much-abused test method, although their attempts at using it were sometimes, from the psychologist's point of view, amusingly clumsy.

[9] See p. 182 _ff._ of reference 2 at end of this book.

One teacher, for example, questioned the children about some ca.n.a.ls and sluices which were in the vicinity, asking what their purpose was and how they worked. Another showed the children some pretty pictures, which she had brought with her for the purpose, and asked questions about them. Showing the picture of a garret, she asked how a garret differs from an ordinary room. One teacher asked whether in building a factory it was best to have the walls thick or thin. As King Edward had just died, another teacher questioned the children about the details of this event, in order to find out whether they were in the habit of reading the newspapers, or understood the things they heard others read.

Other questions related to the names of the streets in the neighborhood, the road one should take to reach a certain point in the vicinity, etc.

Binet notes that many of the questions were special, and were only applicable with the children of this particular school.

The method of proposing the questions and judging the responses was also at fault. The teachers did not adhere consistently to any definite formula in giving a particular test to the different children. Instead, the questions were materially altered from time to time. One teacher scored the identical response differently for two children, giving one child more credit than the other because she had already judged his intelligence to be superior. In several cases the examination was needlessly delayed in order to instruct the child in what he did not know.

The examination ended, quite properly for a teacher's examination, with questions about history, literature, the metric system, etc., and with the recitation of a fable.

A comparison of the results showed hardly any agreement among the estimates of the three teachers. When questioned about the standard that had been taken in arriving at their conclusions, one teacher said she had taken the answers of the first pupil as a point of departure, and that she had judged the other pupils by this one. Another judged all the children by a child of her acquaintance whom she knew to be intelligent.

This was, of course, an unsafe method, because no one could say how the child taken as an ideal would have responded to the tests used with the five children.

In summarizing the result of his little experiment, Binet points out that the teachers employed, as if by instinct, the very method which he himself recommends. In using it, however, they made numerous errors.

Their questions were often needlessly long. Several were "dilemma questions," that is, answerable by _yes_ or _no_. In such cases chance alone will cause fifty per cent of the answers to be correct. Some of the questions were merely tests of school knowledge. Others were entirely special, usable only with the children of this particular school on this particular day. Not all of the questions were put in the same terms, and a given response did not always receive the same score.

When the children responded incorrectly or incompletely, they were often given help, but not always to the same extent. In other words, says Binet, it was evident that "the teachers employed very awkwardly a very excellent method."

The above remark is as pertinent as it is expressive. As the statement implies, the test method is but a refinement and standardization of the common-sense approach. Binet remarks that most people who inquire into his method of measuring intelligence do so expecting to find something very surprising and mysterious; and on seeing how much it resembles the methods which common sense employs in ordinary life, they heave a sigh of disappointment and say, "Is that all?" Binet reminds us that the difference between the scientific and unscientific way of doing a thing is not necessarily a difference in the _nature_ of the method; it is often merely a difference in _exactness_. Science does the thing better, because it does it more accurately.

It was of course not the purpose of Binet to cast a slur upon the good sense and judgment of teachers. The teachers who took part in the little experiment described above were Binet's personal friends. The errors he points out in his entertaining and good-humored account of the experiment are inherent in the situation. They are the kind of errors which any person, however discriminating and observant, is likely to make in estimating the intelligence of a subject without the use of standardized tests.

It is the writer's experience that the teacher's estimate of a child's intelligence is much more reliable than that of the average parent; more accurate even than that of the physician who has not had psychological training.

Indeed, it is an exceptional school physician who is able to give any very valuable a.s.sistance to teachers in the cla.s.sification of mentally exceptional children for special pedagogical treatment.

This is only to be expected, for the physician has ordinarily had much less instruction in psychology than the teacher, and of course infinitely less experience in judging the mental performances of children. Even if graduated from a first-rank medical school, the instruction he has received in the important subject of mental deficiency has probably been less adequate than that given to the students of a standard normal school. As a rule, the doctor has no equipment or special fitness which gives him any advantage over the teacher in acquiring facility in the use of intelligence tests.

As for parents, it would of course be unreasonable to expect from them a very accurate judgment regarding the mental peculiarities of their children. The difficulty is not simply that which comes from lack of special training. The presence of parental affection renders impartial judgment impossible. Still more serious are the effects of habituation to the child's mental traits. As a result of such habituation the most intelligent parent tends to develop an unfortunate blindness to all sorts of abnormalities which exist in his own children.

The only way of escape from the fallacies we have mentioned lies in the use of some kind of refined psychological procedure. Binet testing is destined to become universally known and practiced in schools, prisons, reformatories, charity stations, orphan asylums, and even ordinary homes, for the same reason that Babc.o.c.k testing has become universal in dairying. Each is indispensable to its purpose.

CHAPTER III

DESCRIPTION OF THE BINET-SIMON METHOD

ESSENTIAL NATURE OF THE SCALE. The Binet scale is made up of an extended series of tests in the nature of "stunts," or problems, success in which demands the exercise of intelligence. As left by Binet, the scale consists of 54 tests, so graded in difficulty that the easiest lie well within the range of normal 3-year-old children, while the hardest tax the intelligence of the average adult. The problems are designed primarily to test native intelligence, not school knowledge or home training. They try to answer the question "How intelligent is this child?" How much the child has learned is of significance only in so far as it throws light on his ability to learn more.

Binet fully appreciated the fact that intelligence is not h.o.m.ogeneous, that it has many aspects, and that no one kind of test will display it adequately. He therefore a.s.sembled for his intelligence scale tests of many different types, some of them designed to display differences of memory, others differences in power to reason, ability to compare, power of comprehension, time orientation, facility in the use of number concepts, power to combine ideas into a meaningful whole, the maturity of apperception, wealth of ideas, knowledge of common objects, etc.

HOW THE SCALE WAS DERIVED. The tests were arranged in order of difficulty, as found by trying them upon some 200 normal children of different ages from 3 to 15 years. It was found, for ill.u.s.tration, that a certain test was pa.s.sed by only a very small proportion of the younger children, say the 5-year-olds, and that the number pa.s.sing this test increased rapidly in the succeeding years until by the age of 7 or 8 years, let us say, practically all the children were successful.

If, in our supposed case, the test was pa.s.sed by about two thirds to three fourths of the normal children aged 7 years, it was considered by Binet a test of 7-year intelligence. In like manner, a test pa.s.sed by 65 to 75 per cent of the normal 9-year-olds was considered a test of 9-year intelligence, and so on. By trying out many different tests in this way it was possible to secure five tests to represent each age from 3 to 10 years (excepting age 4, which has only four tests), five for age 12, five for 15, and five for adults, making 54 tests in all.

LIST OF TESTS. The following is the list of tests as arranged by Binet in 1911, shortly before his untimely death:--

_Age 3:_ 1. Points to nose, eyes, and mouth.

2. Repeats two digits.

3. Enumerates objects in a picture.

4. Gives family name.

5. Repeats a sentence of six syllables.

_Age 4:_ 1. Gives his s.e.x.

2. Names key, knife, and penny.

3. Repeats three digits.

4. Compares two lines.

_Age 5:_ 1. Compares two weights.

2. Copies a square.

3. Repeats a sentence of ten syllables.

4. Counts four pennies.

5. Unites the halves of a divided rectangle.

_Age 6:_ 1. Distinguishes between morning and afternoon.

2. Defines familiar words in terms of use.

3. Copies a diamond.