CONCEPTS AND METHODS OF SOCIOLOGY 175
going on, it is difficult to isolate causes or to control conditions with scientific thoroughness. Observation, therefore, and criti- cally established records of observations made in bygone days, must be our main dependence, so far as the accumulation of data is concerned.
Yet in a field so vast, observation itself would be a fruitless toil if it were not directed by scientific rules. Canons of guid- ance we find in the so-called comparative and historical methods. Selecting any social fact, or correlation of facts, observed in any given society, we systematically search for a corresponding fact or correlation in all contemporaneous societies, animal and human, ethnic and civil. This search has one clearly defined object, namely : to determine whether the observed fact is a uni- versal, and therefore an essential, an elementary phenomenon of society, and, if it is not universal, to ascertain just how wide its distribution is. By such research we discover those resem- blances and differences in social phenomena that are the bases of scientific classification.
Having in this manner arrived at a scheme of classification, we use it in subsequent observation precisely as the chemist or the botanist uses the classifications that have been established in his science. We systematically look for the facts and the corre- lations that the classification leads us to anticipate.
In like manner, following the historical method, we search for a given social fact at each stage in the historical evolution of a given society, and thereby determine what social phenomena are continuous.
A complete scientific theory of natural causation is established only when our knowledge becomes quantitatively precise. Often the law that we seek to formulate eludes us until the correlations of phenomena have been determined with mathematical exact- ness. Sociology has unjustly been reproached for neglecting that attention to precision which is the boast of other sciences. The indictment of vagueness may be a true bill against individual sociologists. It is demonstrably not a true bill against sociol- ogy. It is to the scientific students of sociology that the world owes the discovery and development of an inestimably valuable
