But the notion of a “marketplace of ideas,” like that of a free market generally, is predicated on a utopian conception of consumers. In the case of the metaphor of the marketplace of ideas, the utopian assumption is that conversation works by exchange of reasons, with one party offering its reasons, which are then countered by the reasons of an opponent, until the truth ultimately emerges. But conversation is not just used to communicate information. Conversation is also used to shut out perspectives, raise fears, and heighten prejudice.
