Inasmuch as the book aims to illustrate the working of certain factors
in social organization and evolution by the study of concrete problems,
interpretation has been emphasized rather than the social facts
themselves. However, the book is not intended to be a contribution to
sociological theory, and no attempt is made to give a systematic
presentation of theory. Rather, the student's attention is called to
certain obvious and elementary forces in the social life, and he is left
to work out his own system of social theory.

To guide the student in further reading, a brief list of select
references in English has been appended to each chapter. Methodological
discussions and much statistical and historical material have been
omitted in order to make the text as simple as possible. These can be
found in the references, or the teacher can supply them at his
discretion.

The many authorities to whom I am indebted for both facts and
interpretations of facts cannot be mentioned individually, except that I
wish to express my special indebtedness to my former teachers, Professor
Willcox of Cornell and Professors Small and Henderson of the University
of Chicago, to whom I am under obligation either directly or indirectly
for much of the substance of this book. The list of references will also
indicate in the main the sources of whatever is not my own.

CHARLES A. ELLWOOD.

UNIVERSITY OF MISSOURI.