Looking at Forbes' list of the top 100 celebrities (as measured by pay and media exposure), it turns out that there are 26 of these people that I've never heard of, and another 10-15 whom I vaguely recollect but don't really know what they do. If you take out the 20-30 athletes (I am a big sports fan), my ignorance of the actors and pop stars would really be evident. I suspect that the average American could identify a significantly higher percentage of the nonathlete celebrities on the list than I could.

Just as the average American is rationally ignorant about politics because it doesn't interest him much, I am rationally ignorant about Hollywood and pop music stars because most of them don't interest me much (other than the ones who co-star with Randy Barnett, of course!).

The lesson to be learned, if there is one, is that rational ignorance is a universal phenomenon, not limited to the "stupid" unwashed masses. We are all inevitably ignorant about a wide range of topics. Unfortunately, however, popular ignorance about politics probably causes more social harm than academic geeks' ignorance about pop culture.

The highest-ranking celebrity I'd never heard of: Jay-Z, ranked no. 9.