dealing as it does essentially with the individual, is not mainly concerned. It may be stated at once that it is a principal thesis of this essay that this attitude is a fallacious one, and has been responsible for the comparative sterility of the psychological method in sociology. The two fields—the social and the individual—are regarded here as absolutely continuous; all human psychology, it is contended, must be the psychology of associated man, since man as a solitary animal is unknown to us, and every individual must present the characteristic reactions of the social animal if such exist. The only difference between the two branches of the science lies in the fact that ordinary psychology makes no claim to be practical in the sense of conferring useful foresight; whereas sociology does profess to deal with the complex, unsimplified problems of ordinary life, ordinary life being, by a biological necessity, social life. If, therefore, sociology is to be defined as psychology, it would be better to call it practical or applied psychology than social psychology.
The first effect of the complete acceptance of this point of view is to render very obvious the difficulty and immensity of the task of sociology; indeed, the possibility of such a science is sometimes denied. For example, at an early meeting of the Sociological Society, Professor Karl Pearson expressed the opinion that the birth of the science of sociology must await the obstetrical genius of some one man of the calibre of Darwin or Pasteur. At a later meeting Mr. H. G. Wells went farther, and maintained that as a science sociology not only does not but cannot exist. {13}
Such scepticism appears in general to be based upon the idea that a practical psychology in the sense already defined is impossible. According to some this is because the human will introduces into conduct an element necessarily incommensurable, which will always render the behaviour of man subject to the occurrence of true variety and therefore beyond the reach of scientific generalization; according to another and a more deterministic school, human conduct, while not theoretically liable