Retrospectives: The Law of Diminishing Returns
回顾报酬递减法则在经济学分析中的演变，指出其定义模糊、证明薄弱，且缺乏实证支持，引发该法则究竟是便利工具还是分析基础的疑问。
From introductory economics to theoretical papers, the law of diminishing returns is a part of every economist's tool kit. But the evolution of this law in the history of economic analysis reveals more complexity than is perhaps generally understood. Even among those most responsible for its evolution, the law has been loosely defined, and many so-called “proofs” of the law have been weak and incomplete. Moreover, those who expounded the law and its economic implications rarely offered empirical evidence to support it. In fact, economists have offered alternative explanations for rising short-run marginal cost curves and other implications of the law of diminishing returns. This last point raises an interesting question: Have economists used the law of diminishing returns simply for convenience, or is the law fundamental to economic analysis?