抄録
James Buchanan, a founder of public choice, is also a distinguished political economist. The aim of this paper is to give a methodological review of his political economy. It's major promises are as follows. The behavioral posturate of individuals are not only that of homo economicus. Individ-uals, who maximize their utility also cooperate each other in order to seek mutual gain. Pareto optimality criteria is applied to define rules. But since the utility function of each individual is not fully defined by others, a political economist can only use an hypothetical utility function in his inves-tigation. So the appropriateness check of the proposed rule is needed, and the only measure of it is an unanimity approval.
What a political economist can do is not to show a certain end state of each individual's welfare of outcome, but to show a rule under which every one can seek mutual gain. An appraisal of constitutional revolution is the coherent conclusion of his political economy.
