ive life and of the social role of the person. Three great
autobiographies which have inspired the writing of personal narratives
are themselves representative of the different types: Caesar's
_Commentaries_, with his detached impersonal description of his great
exploits; the _Confessions of St. Augustine_, with his intimate
self-analysis and intense self-reproach, and the less well-known _De
Vita Propria Liber_ by Cardan. This latter is a serious attempt at
scientific self-examination. Recently, attention has been directed to
the accumulation of autobiographical and biographical materials which
are interpreted from the point of view of psychiatry and psychoanalysis.
The study _Der Fall Otto Weininger_ by Dr. Ferdinand Probst is a
representative monograph of this type. The outstanding example of this
method and its use for sociological interpretation is "Life Record of an
Immigrant" contained in the third volume of Thomas and Znaniecki, _The
Polish Peasant_. In connection with the _Recreation Survey_ of the
Cleveland Foundation and the _Americanization Studies of the Carnegie
Corporation_, the life-history has been developed as part of the
technique of investigation.

5. The Measurement of Individual Differences

With the growing sense of the importance of individual differences in
human nature, attempts at their measurement have been essayed. Tests for
physical and mental traits have now reached a stage of accuracy and
precision. The study of temperamental and social characteristics is
still in the preliminary stage.

The field of the measurement of physical traits is dignified by the name
"anthropometry." In the nineteenth century high hopes were widely held
of the significance of measurements of the cranium and of physiognomy
for an understanding of the mental and moral nature of the person. The
lead into phrenology sponsored by Gall and Spurzheim proved to be a
blind trail. The so-called "scientific school of criminology" founded by
Cesare Lombroso upon the identification of the criminal type by certain
abnormalities of physiognomy and physique was undermined by the
controlled study made by Charles Goring. At the present time the
consensus of expert opinion is that only for a small group may gross
abnormalities of physical development be associated with abnormal mental
and emotional reactions.

In 1905-11 Binet and Simon devised a series of tests for determining the
mental age of French school children. The pu