刍议现代经济学的理性假设

On the Rational Hypothesis of Modern Economics

经济学是关于理性选择的学科,不同理性前提的内涵构成了不同经济学体系的基础。主流经济学以完全理性作为其前提假设,并得出行为人可以在诸多决策方案中进行最优选择的结论;但是,完全理性假设不仅在真实性方面存在缺陷,而且在逻辑推理上和实践检验中都遭到质疑。实际上,行为人的理性是有限的,在此前提下,新制度经济学、演化经济学和行为经济学等经济学分支构建了自己的学科体系并创建了行为人在有限理性条件下的真实选择模式。

Economics is a subject about rational choices. Different economic systems are constructed on the basis of different rational hypotheses. Mainstream economics, based on the hypothesis of perfect rationality, concludes that agents can attain the optimal object out of all the choices. However, perfect rationality is not true, and it fails in the logical reasoning and practical examination. Actually, agents have only limited rationality. With this conclusion as a presupposition, various branches of economics, such as the new institutional economics, evolutionary economics and behavior economics, etc. , have established their respective disciplinary systems and constructed their agents＇ real choice models.