Political science is the scientific study of politics. It is a social science dealing with systems of governance and power, and the analysis of political activities, political thought, political behavior, and associated constitutions and laws. Modern political science can generally be divided into the three subdisciplines of comparative politics, international relations, and political theory. Other notable subdisciplines are public policy and administration, domestic politics and government, political economy, and political methodology. Furthermore, political science is related to, and draws upon, the fields of economics, law, sociology, history, philosophy, human geography, political anthropology, and psychology. Political science is methodologically diverse and appropriates many methods originating in psychology, social research, and political philosophy. Approaches include positivism, interpretivism, rational choice theory, behaviouralism, structuralism, post-structuralism, realism, institutionalism, and pluralism. Political science, as one of the social sciences, uses methods and techniques that relate to the kinds of inquires sought: primary sources, such as historical documents and official records, and secondary sources, such as scholarly journal articles, survey research, statistical analysis, case studies, experimental research, and model building.