Judge Posner makes quick work of two lousy hypotheses about the media.
It's said that Americans are becoming more politically polarized: just look at the media. But Judge Posner argues that the polarization of the media has nothing to do with polarization of the public.
The current tendency to political polarization in news reporting is thus a consequence of changes not in underlying political opinions but in costs, specifically the falling costs of new entrants. The rise of the conservative Fox News Channel caused CNN to shift to the left. CNN was going to lose many of its conservative viewers to Fox anyway, so it made sense to increase its appeal to its remaining viewers by catering more assiduously to their political preferences.
It's further said, by some in the mainstream media especially, that bloggers should be distrusted because they are unsupervised. Judge Posner:
The charge by mainstream journalists that blogging lacks checks and balances is obtuse. The blogosphere has more checks and balances than the conventional media; only they are different. The model is Friedrich Hayek's classic analysis of how the economic market pools enormous quantities of information efficiently despite its decentralized character, its lack of a master coordinator or regulator, and the very limited knowledge possessed by each of its participants.