materials, however, but as a systematic treatise. On
the other hand, the excerpts which make up the body of the book are not
to be regarded as mere illustrations. In the context in which they
appear, and with the headings which indicate their place in the volume,
they should enable the student to formulate for himself the principles
involved. An experience of some years, during which this book has been
in preparation, has demonstrated the value to the teacher of a body of
materials that are interesting in themselves and that appeal to the
experience of the student. If students are invited to take an active
part in the task of interpretation of the text, if they are encouraged
to use the references in order to extend their knowledge of the
subject-matter and to check and supplement classroom discussion by their
personal observation, their whole attitude becomes active rather than
passive. Students gain in this way a sense of dealing at first hand with
a subject-matter that is alive and with a science that is in the making.
Under these conditions sociology becomes a common enterprise in which
all members of the class participate; to which, by their observation and
investigation, they can and should make contributions.

The first thing that students in sociology need to learn is to observe
and record their own observations; to read, and then to select and
record the materials which are the fruits of their readings; to
organize and use, in short, their own experience. The whole organization
of this volume may be taken as an illustration of a method, at once
tentative and experimental, for the collection, classification, and
interpretation of materials, and should be used by students from the
very outset in all their reading and study.

Social questions have been endlessly discussed, and it is important that
they should be. What the student needs to learn, however, is how to get
facts rather than formulate opinions. The most important facts that
sociologists have to deal with are opinions (attitudes and sentiments),
but until students learn to deal with opinions as the biologists deal
with organisms, that is, to dissect them--reduce them to their component
elements, describe them, and define the situation (environment) to which
they are a response--we must not expect very great progress in
sociological science.

It will be noticed that every single chapter, except the first, falls
naturally into four parts; (1) the introdu