Do Metaphors Affect Economic Theory?

Over the last few decades, theoretical discussions about metaphors have appeared with increasing frequency in the literature and, during the last fifteen years or so, such discussions have become more and more common in the methodology of economics. But what exactly is a metaphor? According to a tradition which dates back to Aristotle, a metaphor is the attribution to one object, A, of the name (and indirectly of the qualities) of another object, B, while this name or these qualities do not properly or normally belong to A. Thus, a metaphor is present when a term used to describe (or even to name) A is a term which is already commonly used to name B (quite a different kind of entity). Defined in such a way, one must admit that metaphors are frequently found in economics as well as in other sciences. Let us consider, for example, a term like ‘elasticity’ which is extensively used by economists. According to the ordinary dictionary definition, this word designates a property of bodies by which they recover their initial form after having been submitted to a pressure; in a less technical sense, it refers to the flexibility of some bodies or to their responsiveness to pressures.