A number of studies which apply a microeconomic approach to other social science are increasing in recent years. These studies are widespread to politics, sociology, anthropology and generally called Rational Choice Theory (RCT). There are many studies especially in politics, and researchers who support RCT assert how well RCT work in political analysis. Rational Choice Theory is fundamentally based on the idea that an actor will generally choose an option he supposes is the best when he has several options to choose, and logically explains political phenomena as a consequence of rational action of individual. In politics, the methodology of RCT started to be applied to political analysis in 1950s, mainly set in America, and be introduced by economic researchers like K. J. Arrow, J. M. Buchanan. Therefore, RCT had strong influence from these economic researchers and was close to microeconomic approach especially at the beginning. RCT originally has 6 characters which are as same as microeconomic method; (1) methodological individualism, (2) deductionism, (3) purpose-rationality, (4) preference hypothesis, (5) constraint hypothesis, and (6) utility maximum. These characters show that RCT has similarity to neoclassical economic theory of 1930s through ideas of K. J. Arrow and J. M Buchanan. However, recent studies of rational choice analysis criticize these above assumptions because they are too unrealistic to apply to social life and are apart from neoclassical economic theory. According to this criticism, RCT changed its methodology to looser assumptions. Moreover, RCT in politics is combined with new institutionalism which occurs in late-1970s to 80s in America. RCT in 1980s to 90s emphasizes an importance of governments, rules and customs in each situation. Although RCT still has plausible solutions to answer political problems, it shows us a limit of neoclassical methodology to apply to social science.
