"Intelligence" at best is an assumptive construct -- the
word’s meaning has never been clear. 61) There is more agreement on the kinds
of behavior referred to by the term than there is on how to interpret or
classify them. But it is generally agreed that a person who has high
intelligence is one who can grasp ideas readily, make distinctions, reason
logically, and use verbal and mathematical symbols in solving problems. An
intelligence test is a rough measure of a child’s capacity for learning,
particularly for learning the kinds of things required in school. It does not
measure character, social adjustment, physical endurance, manual skills, or
artistic abilities. It is not supposed to -- it was not designed for such
purposes. 62) To criticize it for such failure is roughly comparable to
criticising a thermometer for not measuring wind velocity.
The other thing we should notice is that the assessment of the
intelligence of any subject is essentially a comparative affair.
63) Now since the assessment of intelligence is a comparative matter we
must be sure that the scale with which we are comparing our subjects provides a
"valid" or "fair" comparison. It is here that some of the difficulties which
interest us begin. Any test performed involves at least three factors: the
intention to do one’s best, the knowledge required for understanding what you
must do, and the intellectual ability to do it. 64) The first two must be
equal for all who are being compared, if any comparison in terms of intelligence
is to be made. In school populations in our culture these assumptions can be
made fair and reasonable, and the value of intelligence testing has been proved
thoroughly. Its value lies, of course, in its providing a satisfactory basis for
prediction. Nobody is in the least interested in the marks a little child gets
on his test; what we are interested in is whether we can conclude from his mark
on the test that the child will do better or worse than other children of his
age at tasks which we think require "general intelligence". 65) On the whole,
such a conclusion can be drawn with a certain degree of confidence, but only if
the child can be assumed to have had the same attitude towards the test as the
other with whom he is being compared, and only if he was not punished by lack of
relevant information which they possessed.