Some of us narrow our exposure to serendipitous and challenging information by focusing our attention on Web sites and online communities that agree with us -- Democrats following Obama and Tea Party members following Palin. Eli Pariser argues that, even if we want to see challenging opinions, search engines send us biased results -- things we and our friends like.
Then there is good old fashioned censorship as exemplified by the CubaNews group on Yahoo. The CubaNews tagline is "News and information about Cuba today." It was established in August 2000, has 1,958 members, and is moderated.
When I started this blog, the CubaNews moderator, Walter Lippmann, read some early posts and attacked them. I responded and also suggested that he read a report I had written earlier in the year. I had fruitful exchanges with some of the CubaNews readers and in comments to posts on this blog.
Then someone sent me an email saying Lippmann had censored his post to CubaNews. When I asked Lippmann about that, he did not answer, and now he rejects my posts to CubaNews as well. He has sent me a few subsequent comments, and I have published them without hesitation. Critics of the Castro government accuse it of propagandizing and stifling free expression -- CubaNews' behavior lends support to that claim.
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Update 7/15/2013
Ironically, all Cuban government publications are not as heavy handed as CubaNews. Isbel Diaz Torres of Havana Times has written a post on the varying degree of censorship on Government Web sites. For example, Granma does not allow comments, period, while Juventud Rebelde "offers a fairly broad space for comments by readers, who can express opinions that are diametrically opposed to those presented by the author of a given article."
The post discusses the comment-censorship policy of several other sites and I take the variation to be a good sign -- the site publishers have discretion.