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 Bell curve? 

""If there is any difference in ""desirability"", the bell curve of a normal distribution predicts that most experiences will involve average desirability, with roughly equal occurrences of excellence and gross inadequacy."" I disagree: I think it would tend to follow a Pareto distribution with 20% of the books in a genre accounting for 80% of the worthiness of the genre as a whole. I think this is probably closer to what Sturgeon had in mind. Merlin "