The constitutional justification for intellectual property is welfarist. In theory, it increases social welfare by solving market failures caused by free riding on innovation and transaction costs. But intellectual property rhetoric is metaphorical. Among other things, we compare intellectual property owners to farmers, infringers to pirates, and abusers to trolls. These metaphors obscure the welfarist justification for intellectual property by describing it as an expression of moral values. In order to understand intellectual property, we should stop using intellectual property metaphors.
Frye, Brian L, IP as Metaphor (March 28, 2015).