From the PREFACE:
"Careful studies of offenders make group-types stand out with
distinctness.á Very little advancement in the treatment of
delinquents or criminals can be expected if typical
characteristics and their bearings are not understood.á The group
that our present work concerns itself with is comparatively
little known, although cases belonging to it, when met, attract
much attention.á It is to all who should be acquainted with these
striking mental and moral vagaries, particularly in their
forensic and psychological significances, that our essay is
addressed.á In some cases vital for the administration of
justice, an understanding of the types of personality and of
behavior here under discussion is a prime necessity.

The whole study of characterology or the motivation of conduct is
extremely new, and there are many indications of immense values
in uncovered fields.á Some appreciation of this fact may be
gained from the following pages which show the possibility of
tracing one form of behavior to its source.

We have laid under contribution practically the entire literature
on the subject, almost none of which is in English, and also the
thorough-going longitudinal case studies made by the Juvenile
Psychopathic Institute of Chicago.á In the latter material there
was found much of value bearing upon the subject of lying, false
accusation, and swindling of pathological character."