nswer is given, do not fail to unfold the paper
and let the subject view the result.

SCORING. The test is passed _if the rule is grasped by the time the
sixth sheet is reached_; that is, the subject may pass after five
incorrect responses, provided the sixth is correct and the governing
rule can then be given. It is not permissible to ask for the rule until
all six parts of the experiment have been given. Nothing must be said
which could even suggest the operation of a rule. Often, however, the
subject grasps the principle after two or three steps and gives it
spontaneously. In this case it is unnecessary to proceed with the
remaining steps.

REMARKS. This test was first used by the writer in a comparative study
of the intellectual processes of bright and dull boys in 1905, but it
was not standardized until 1914. Rather extensive data indicate that it
is a genuine test of intelligence. Of 14-year-old school children
testing between 96 and 105 I Q, 59 per cent passed this test; of
14-year-olds testing below 96 I Q, 41 per cent passed; of those testing
above 105, 71 per cent passed. That is, the test agrees well with the
results obtained by the scale as a whole. Of "average adults" only
10 per cent fail; and of "superior adults," fewer than 5 per cent. As a
rule, the higher the grade of intelligence, the fewer the steps
necessary for grasping the rule. Of the superior adults, only
35 per cent fail to get the rule as early as the end of the fourth step.

The test is little affected by schooling, and apart from differences in
intelligence it is little influenced by age. Other advantages of the
test are the keen interest it always arouses and its independence of
language ability. It has been used successfully with immigrant subjects
who had been in this country but a few months.

We have named the experiment an "induction test." It might be supposed
that the solution would ordinarily be arrived at by deduction, or by an
_a-priori_ logical analysis of the principle involved. This, however, is
rarely the case. Not one average adult out of ten reasons out the
situation in this purely logical manner. It is ordinarily only after one
or more mistakes have been made and have been exposed by the examiner
holding up the unfolded paper to view that the correct principle is
grasped. In the absence of deductive reasoning the subject must note
that each unfolded sheet contains twice as many holes as the previous
one, and must infer