Some well-known economists suggest that a good economist should act like an engineer, a surgeon, a dentist, or even a plumber. These metaphors are useful in helping economists reflect the nature of economics and their role in society. But which is the most sensible one? This paper argues that economists should be playing all these roles and more, because economics is not a single entity, and each entity has separate goals, methods, and boundaries. To take this multiplicity of roles into account, this paper argues that in addition to the traditional boundary that delineates the disciplinary domain of economics against other sciences, an overarching boundary between economic science and applied policy needs to be recognized. It then examines Esther Duflo’s “economist as plumber” metaphor and suggests that a better metaphor for Duflo’s purpose would be “general contractor,” a metaphor that, if accepted, would suggest radical change in training applied policy economists.

中文翻译：

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经济学家是科学家、工程师还是水管工？

一些著名的经济学家建议，一个好的经济学家应该像工程师、外科医生、牙医，甚至是管道工。这些比喻有助于经济学家反映经济学的本质及其在社会中的作用。但哪个是最明智的？本文认为经济学家应该扮演所有这些角色，甚至更多，因为经济学不是一个单一的实体，每个实体都有不同的目标、方法和界限。考虑到这种多重角色，本文认为，除了将经济学学科领域与其他科学划定的传统边界之外，还需要认识到经济科学与应用政策之间的总体边界。