There are certain features of this volume which it is important that the reader should have in mind from the beginning, since the volume represents a departure from the traditional treatment of the subject.
In the first place, the treatment is not intended to be comprehensive, nor absolutely systematic. Certain topics, for example, racial psychology, are omitted because, in the opinion of the author, the present state of our information on these topics is such that their treatment in an elementary and general text would be useless. Topics have been selected which are central in their interest, vital in their relation to the general subject, and definite enough to constitute together a starting point from which further progress may be made. Concrete facts of organization are, in the main, put first, and generalizations of principles last, although the principles are to some extent developed in the treatment of data, and the later generalizations are limited in scope.
In the second place, the treatment of social psychology here given departs from tradition in that it is not an attempt to develop the subject on the basis of a single explanatory principle (such as instinct, imitation, or the "crowd mind"), but bases it on the total results of general psychology. This, in the author's opinion, is the most important feature of the volume, and the source of such value as it may have. On the other hand, the treatment is conservative in that it makes no use of "unconscious mental processes," "the unconscious mind," or other popular substitutes for scientific principles. Psychology is fully competent to explain all mental processes, social as well as individual, without recourse to mysticism or pseudo-psychology.
In the third place, the method and viewpoint of the presentations are such that some readers will be inclined to say at certain points: "This is not psychology; it is biology" (or anthropology, or philosophy, or archaeology, etc.). Actually, the book makes use of data from all of these subjects, but always from the viewpoint of psy-
( 8) -chology, and the variety of subjects from which the data are brought together is perhaps the best justification for the claim that the treatise is not in any one of these subjects, nor merely a mosaic of them, but is actually and vitally psychology, in which all human sciences find their meeting point.
In the fourth place, the method of presentation is dogmatic. In fact, it is intentionally so, and its real imperfection in this respect lies in the fact that it falls away, in various places, from this level. The full justification for this dogmatic method will be found in the final chapter of the volume. The author has no doctrines which he wishes to "put over." If the presentation stirs the reader to lively questioning and opposition, it will lead him to further critical observation and evaluation of data and theories in this field: and so the real purpose of the text will have been accomplished.