n of invention in
the higher thought processes. In one form or another it is present in
all intellectual activity; in the creation and use of language, in art,
in social adjustments, in religion, and in philosophy, as truly as in
the domains of science and practical affairs. Certainly this is true if
we accept Mason's broad definition of invention as including "every
change in human activity made designedly and systematically."[78] From
the psychological point of view, perhaps, Mason is justified in looking
upon the great inventor as "an epitome of the genius of the world." To
develop a Krag-Joergensen from a bow and arrow, a "velvet-tipped"
lucifer match from the primitive fire-stick, or a modern piano from the
first crude, stringed, musical instrument has involved much the same
intellectual processes as have been operative in transforming fetishism
and magic into religion and philosophy, or scattered fragments of
knowledge into science.

[78] Otis T. Mason: _The Origins of Inventions_. (London, 1902.)

Psychologically, invention depends upon the constructive imagination;
that is, upon the ability to abstract from what is immediately present
to the senses and to picture new situations with their possibilities and
consequences. Images are united in order to form new combinations.

As we have several times emphasized, the decisive intellectual
differences among human beings are not greatly dependent upon mere sense
discrimination or native retentiveness. Far more important than the raw
mass of sense data is the correct shooting together of the sense
elements in memory and imagination. This is but another name for
invention. It is the synthetic, or apperceptive, activity of the mind
that gives the "seven-league boots" to genius. It is, however, a kind of
ability which is possessed by all minds to a greater or less degree. Any
test has its value which gives a clue, as this test does, to the
subject's ability in this direction.

The test was devised by the writer and used in 1905 in a study of the
intellectual processes of bright and dull boys, but it was not at that
time standardized. It has been found to belong at a much higher mental
level than was at first supposed. Only an insignificant number pass the
test below the mental age of 14 years, and about two thirds of "average
adults" fail. Of our "superior adults" somewhat more than 75 per cent
succeed. Formal education influences the test little or not at all, the
un