rpose of the mental
measurements was to gauge innate mental capacity. Therefore the tests
excluded material which had to do with special social experience. With
their introduction into the United States certain revisions and
modifications, such as the Goddard Revision, the Terman Revision, the
Yerkes-Bridges Point Scale, were made in the interests of
standardization. The application of mental measurements to different
races and social classes raised the question of the extent to which
individual groups varied because of differences in social experience.
While it is not possible absolutely to separate original tendencies from
their expression in experience, it is practicable to devise tests which
will take account of divergent social environments.

The study of volitional traits and of temperament is still in its
infancy. Many recent attempts at classification of temperaments rest
upon as impressionistic a basis as the popular fourfold division into
sanguine, melancholic, choleric, and phlegmatic. Two of the efforts to
define temperamental differences rest, however, upon first-hand study of
cases. Dr. June E. Downey has devised a series of tests based upon
handwriting material for measuring will traits. In her pamphlet _The
Will Profile_ she presents an analysis of twelve volitional traits:
revision, perseverance, co-ordination of impulses, care for detail,
motor inhibition, resistance, assurance, motor impulsion, speed of
decision, flexibility, freedom from inertia, and speed of movement. From
a study of several hundred cases she defined certain will patterns which
apparently characterize types of individuals. In her experience she has
found the rating of the subject by the will test to have a distinct
value in supplementing the test for mentality.

Kraepelin, on the basis of his examination of abnormal mental states,
offers a classification of types of psychopathic personalities. He
distinguishes six groups: the excitable, the unstable, the psychopathic
trend, the eccentric, the anti-social, and the contentious. In
psychoanalysis a simpler twofold division is frequently made between the
_introverts_, or the "introspective" and the _extroverts_, or the
"objective" types of individual.

The study of social types is as yet an unworked field. Literature and
life surround us with increasing specializations in personalities, but
attempts at classification are still in the impressionistic stage. The
division suggested by T