General Value Of The Method
In a former chapter we have noted certain imperfections of the scale devised
by Binet and Simon; namely, that many of the tests were not correctly located,
that the choice of tests was in a few cases unsatisfactory, that the directions
for giving and scoring the tests were sometimes too indefinite, and that the upper
and lower ranges of the scale especially stood in need of extensions and
corrections. All of these faults have b
en quite generally admitted. The
method itself, however, after being put to the test by psychologists of
all countries and of all faiths, by the skeptical as well as the
friendly, has amply demonstrated its value. The agreement on this point
is as complete as it is regarding the scale's imperfections.
The following quotations from prominent psychologists who have studied
the method will serve to show how it is regarded by those most entitled
to an opinion:--
There can be no question about the fact that the Binet-Simon
tests do not make half as frequent or half as great errors in
the mental ages (of feeble-minded children) as are included in
gradings based on careful, prolonged general observation by
experienced observers.
All of the different authors who have made these researches
(with Binet's method) are in a general way unanimous in
recognizing that the principle of the scale is extremely
fortunate, and all believe that it offers the basis of a most
useful method for the examination of intelligence.
It serves as a relatively simple and speedy method of securing,
by means accessible to every one, a true insight into the
average level of ability of a child between 3 and 15 years of
age.
That, despite the differences in race and language, despite the
divergences in school organization and in methods of
instruction, there should be so decided agreement in the
reactions of the children--is, in my opinion, the best
vindication of the _principle_ of the tests that one could
imagine, because this agreement demonstrates that _the tests do
actually reach and discover the general developmental conditions
of intelligence_ (so far as these are operative in
public-school children of the present cultural epoch), and not
mere fragments of knowledge and attainments acquired by
chance.
It is without doubt the most satisfactory and accurate method of
determining a child's intelligence that we have, and so far
superior to everything else which has been proposed that as yet
there is nothing else to be considered.
The value of the method lies both in the swiftness and the accuracy with
which it works. One who knows how to apply the tests correctly and who
is experienced in the psychological interpretation of responses can in
forty minutes arrive at a more accurate judgment as to a subject's
intelligence than would be possible without the tests after months or
even years of close observation. The reasons for this have already been
set forth. The difference is something like that between measuring a
person's height with a yardstick and estimating it by guess. That this
is not an unfair statement of the case is well shown by the following
candid confession by a psychologist who tested 200 juvenile delinquents
brought before Judge Lindsey's court:--
As a matter of interest I estimated the mental ages of 150 of my
subjects before testing them. In 54 of the estimates the error
was not more than one year in either direction; 70 of the
subjects were estimated too high, the average error being
2 years and 7 months; 26 of the subjects were estimated too low,
the average error being 2 years and 2 months. _These figures
would seem to imply that an estimate with nothing to support it
is wholly unreliable, more especially as many of the estimates
were four or five years wide of the mark.
Criticisms of the Binet method have also been frequently voiced, but
chiefly by persons who have had little experience with it or by those
whose scientific training hardly justifies an opinion. It cannot be too
strongly emphasized that eminence in law, medicine, education, or any
other profession does not of itself enable any one to pass judgment on
the validity of a psychological method.