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


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


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.