THE SCOPE OF SOCIOLOGY 211
of persons. Just as the chemist must very early get familiar with certain primary facts about his "elements," their specific gravity, their atomicity, their relation to oxygen, etc., etc. ; so the sociologist, whether amateur or professional, must early get a working knowledge of the essential peculiarities of persons. Sociology accordingly amounts to a technique for detecting, classifying, criticising, measuring, and correlating human inter- ests, first with reference to their past and present manifesta- tions, and second with reference to their indications for the future. The sociological study that is provided for in university courses is not like the instruction in law, which is calculated to make men the most effective practitioners under the code that now exists. All our programs of sociological study are more like the courses in pure and applied mathematics which a West Point student is obliged to take. They are not expected to give him specific knowledge of the situations which he may encounter in a campaign. They are supposed to make him familiar with the elements out of which all possible military situations are composed, with the means of calculating all possible relationships that can occur between these elements, and with the necessary processes of controlling theoretical and practical dealings with these elements under any circumstances whatsoever.
Every real social problem throws upon the sociologist who undertakes to deal with it the task of calculating a unique equation of interests. General sociology is a preparation for judging a concrete combination of interests very much as general training in physiology and pathology and clinical practice pre- pares the physician for diagnosis of the new cases which will occur in his practice. He may never meet precisely the same combinations of conditions and symptoms which he has con- sidered in the course of his preparatory training, but he is sup- posed to have become familiar at least with all the general types of conditions and symptoms which can occur, and to have acquired ability to form reliable judgments on the specific nature of any new combinations of them which he may encounter.
Suppose, for instance, we are dealing with the practical prob- lems of law-enforcement in a particular town in a state which has
