A very common mistake which the child makes is to give differences instead of similarities. This tendency is particularly strong if [test 5, year VII] (giving differences), has been given earlier in the sitting, but it happens often enough in other cases also to suggest that finding differences is, to a much greater extent than finding similarities, the child’s preferred method of making a comparison. When a difference is given, instead of a similarity, we say: “No, I want you to tell me how they are alike. In what way are ... and ... alike?” Unless the child is of rather low intelligence level this is sufficient, but the mentally retarded sometimes continue to give differences persistently in spite of repeated admonitions, or if they cease to do so for one or two comparisons, they are likely to repeat the mistake in the latter part of the test.
Scoring. The test is passed if a likeness is given in two out of four comparisons. We accept as satisfactory any real likeness, whether fundamental or superficial, though, of course, the more essential the resemblance, the better indication it is of intelligence. The following are samples of satisfactory and unsatisfactory answers:—[58]
(a) Wood and coal
Satisfactory. “Both burn.” “Both keep you warm.” “Both are used for fuel.” “Both are vegetable matter.” “Both come from the ground.” “Can use them both for running engines.” “Both hard.” “Both heavy.” “Both cost money.”
Of 80 correct answers, 64, or 80 per cent, referred in one way or another to combustibility.
Unsatisfactory. Most frequent is the persistent giving of a difference instead of a similarity. This accounts for a little over half of all the failures. About half of the remainder are cases of inability to give any response. Incorrect statements with regard to color are rather common. Sample failures of this type are: “Both are black,” or “Both the same color.” Other failures are: “Both are dirty on the outside;” “You can’t break them;” “Coal burns better;” “Wood is lighter than coal,” etc.
(b) An apple and a peach
Satisfactory. “Both are round.” “Both the same shape.” “They are about the same color.” “Both nearly always have some red on them.” “Both good to eat.” “Can make pies of both of them.” “Both can be cooked.” “Both mellow when they are ripe.” “Both have a stem” (or seeds, skin, etc.). “Both come from trees.” “Can be dried in the same way.” “Both are fruits.” “Both green (in color) when they are not ripe.”
Of 82 correct answers, 25 per cent mention color; 25 per cent, form; 22 per cent, edibility; 20 per cent, having stem, seed, or skin; and 5 per cent, that both grow on trees.
Unsatisfactory. “Both taste the same.” “Both have a lot of seeds.” “Both have a fuzzy skin.” “An apple is bigger than a peach.” “One is red and one is white,” etc.
Again, over 50 per cent of the failures are due to giving differences and about 18 per cent to silence.
(c) Iron and silver
Satisfactory. “Both are metals” (or mineral). “Both come out of the ground.” “Both cost money.” “Both are heavy.” “Both are hard.” “Both can be melted.” “Both can be bent.” “Both used for utensils.” “You manufacture things out of both of them.” “Both can be polished.”
These are named most frequently in the following order: (1) hardness, (2) origin from the ground, (3) heaviness, (4) use in making things.
Unsatisfactory. “Both thin” (or thick). “Sometimes they are the same shape.” “Both the same color.” “A little silver and lots of iron weigh the same.” “Both made by the same company.” “They rust the same.” “You can’t eat them” (!)[59]
Of 60 failures, 32 were due to giving differences and 14 to silence or unwillingness to hazard a reply.
(d) A ship and an automobile
Satisfactory. “Both means of travel.” “Both go.” “You ride in them.” “Both take you fast.” “They both use fuel.” “Both run by machinery.” “Both have a steering gear.” “Both have engines in them.” “Both have wood in them.” “Both can be wrecked.” “Both break if they hit a rock.”
About 45 per cent of the answers are in terms of running or travel, 37 per cent in terms of machinery or structure, the rest scattered.
Unsatisfactory. “Both black” (or some other color). “Both very big.” “They are made alike.” “Both run on wheels.” “Ship is for the water and automobile for the land.” “Ship goes on water and an automobile sometimes goes in water.” “An auto can go faster.” “Ship is run by coal and automobile by gasoline.”
Of 51 failures, 32 were due to giving differences and 14 to failure to reply.
Remarks. The test of finding similarities was first used by Binet in 1905. Our results show that it is fully as satisfactory as the test of giving differences. The test reveals in a most interesting way one of the fundamental weaknesses of the feeble mind. Young normal children, say of 7 or 8 years, often fail to pass, but it is the feeble-minded who give the greatest number of absurd answers and who also find greatest difficulty in resisting the tendency to give differences.[60]
VIII, 5. Giving definitions superior to use
Procedure. The words for this year are balloon, tiger, football, and soldier. Ask simply: “What is a balloon?” etc.
If it appears that any of the words are not familiar to the child, substitution may be made from the following: automobile, battle-ship, potato, store.
Make no comments on the responses until all the words have been given. In case of silence or hesitation in answering, the question may be repeated with a little encouragement; but supplementary questions are never in order. Ordinarily there is no difficulty in securing a response to the definition test of this year. The trouble comes in scoring the response.
Scoring. The test is passed if two of the four words are defined in terms superior to use. “Superior to use” includes chiefly: (a) Definitions which describe the object or tell something of its nature (form, size, color, appearance, etc.); (b) definitions which give the substance or the materials or parts composing it; and (c) those which tell what class the object belongs to or what relation it bears to other classes of objects.
It is possible to distinguish different grades of definitions in each of the above classes. A definition by description (type a) may be brief and partial, mentioning only one or two qualities or characteristics, or it may be relatively rich and complete. Likewise with definitions of type b. Classificatory definitions (type c) are of particularly uneven value, the lowest order being those which subsume the object to be defined under a remote class and give few if any characteristics to distinguish it from other members of the same class; as, for example, “A football is a thing you can have fun with,” or, “A soldier is a person.” The best classificatory definitions are those which subsume the object under the next higher class and give the more essential traits (perhaps a number of them) which distinguish the object from others of the class named; as, for example, “A tiger is a large animal like a cat; it lives in the jungle and eats men and other animals,” or, “A soldier is a man who goes to war.” These shades of distinction give interesting and valuable clues to the maturity and richness of the apperceptive processes, but for purposes of scoring it is necessary merely to decide whether the definition is given in terms superior to use.