The analytical approach used in this course, based on the recognition that human action originates in individuals, is known as methodological individualism. The opposite approach, methodological collectivism, begins with the assumption that action is rooted in society or particular social groupings. The latter view has a number of failings. As we have seen, its basic assumption of group action is not justified by our experience. All apparent instances of social action, when examined closely, can be better understood as resulting from actions of individuals, either in communication or in cooperation.

The approach of methodological collectivism also fails to explain adequately many significant specific observations of human action ()—observations which are easily explained and even predicted within an individualist methodological framework. The methodological collectivist can at best offer ad hoc explanations for such facts. If the ultimate test of a scientific hypothesis is whether it can predict what has not yet been observed, then the collectivist hypothesis fails that test, while methodological individualism clearly satisfies it. To the methodological collectivist, these observations appear as "exceptional" phenomena, requiring supplementary explanations. This view therefore fails another important scientific test, by introducing extraneous assumptions not necessitated by experience (pp. 1.3:78-9). In any case, methodological collectivism fails to relate human action to the nature of the acting entity or entities—and therefore does not truly explain that action. (Regarding explanation, see p. 1.4:18.)