Deliberation as self-discovery and institutions for political speech

We present a game-theoretic model of the social dynamics of belief change in which the (relevant) logically non-omniscient audience becomes convinced that the speakers' messages are 'true' because its own prior beliefs logically entail them, rather than - as in cheap-talk models - because the speaker is (endogenously) trustworthy. We characterize the equilibria of the game and consider how their aggregate informational properties change with the variation in the institutions determining the ability of the speakers to reach their audience. We find that for plausible restrictions on the distribution of arguments and on the corresponding policy preferences in society, the informationally optimal institutions are first-best implementable, inegalitarian with respect to the resource allocation across speakers, and assign priority to the (more) extreme argument- and policy-holders.