What is a rational person?

In layman's terms, a rational person is one who has a clear goal and knows how to achieve it, one who is shrewd and acts logically. Western economics, on the other hand, defines the above attributes theoretically: a person is rational if his preferences are complete and transmissible. (As for the fact that some books point out another element of rational behavior - reflexivity - it is only for the purpose of formal rigor of the analytical process, which contributes to the conduct of normative research). From the above statement, we understand that the definition of rational behavior given by economics from a scientific point of view is the same as the common understanding in our daily life, but the theoretical understanding is more explicit, clear and rigorous, which helps to carry out in-depth research.

Western economics reviewed in our textbook belongs to the mainstream Western economic theory, and one of their ****same characteristics is to analyze people's rational behavior. Therefore, if some people's behavior is irrational, then the Western economics presented in the textbook cannot be analyzed. If a person is akin to a small child with an unenlightened mind, or a minority of people with weak computational skills and judgment, who act in ways that have no clear logic, or, to be more precise, who act in ways that are logically different from rationality, then Western economics based on the principle of rationality can't analyze how they make their choices.

Rationality and economic man are two different things. An egoist is rational, and an altruist can be rational. If the individuals analyzed by economics are both rational and self-interested, economics calls them economic beings.

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