Your excerpt does not make clear that Jefferson was discussing the education of women, and in the late 18th & early 19th centuries "educated" women did read a lot of novels, satirized by Jane Austen in "Northanger Abbey." So did Jefferson, as one can see by his later comments from this letter. He sees some use for fiction, that the best can be "useful vehicles of a sound morality" or "useful for forming style and taste." Given the times and the society he was living in, his comments are not all that off base.
I make the same sorts of arguments against television, even now. I think that reading fiction is excellent practice for discussing and writing fiction, and that discussing fiction is excellent practice for analytical thinking, which can be applied in all sorts of arenas. Writing fiction, meanwhile, is excellent practice for writing of any type, which is a useful skill.
My reading of Jefferson in this passage (and I haven't read the rest of it, as Karen apparently has) is that his belief is that spending time merely for entertainment is not a particularly productive use of time.
He said, preparing to post his comment on a friend's blog.
Far be it from me to suggest that his comments are off base -- my intention is not to lampoon Jefferson. But it's striking how similar his attack on novels is to contemporary attacks on TV or video games -- which also are often targeted in the context of a particular group (boys, say, for video games) and usually also hasten at the end to tack on a few exceptions to the rule ("but of course not Sesame Street").
It's clear from Jefferson's lukewarm praise for the few novels he can bring himself to endorse that he doesn't really get the new medium. "Some few, modeling their narratives, although fictitious, on the incidents of real life, have been able to make them interesting and useful vehicles of a sound morality" -- that is, if novels are sufficiently didactic, they may, if you hold your nose, almost approach the virtues of biography. "Such, I think, are Marmontel's new moral tales, but not his old ones, which are really immoral" -- I haven't read Marmontel, but the metric here is a bit dubious.
Jefferson writes this the year Austen died, but no mention of her, or Cervantes, or Henry Fielding. One suspects he might find Austen too morally ambiguous and paying undue attention to emotional trivia. One suspects he might prefer Richardson to Fielding, not on aesthetic merit but as a safer pedagogical tool for shaping the morality of vulnerable young minds.
He does not in fact say novels are "useful in forming style and taste" -- only that a moderate does of poetry may be (but too much poetry should not be indulged)! Indeed, one has the strong suspicion that he would recoil from the notion that faux-biographical fictional prose would be any kind of model for style, or guide to taste. None of the people in his laundry list of models of high literature are novelists -- Shakespeare and Moliere never wrote any novels.
Again, this is not to condemn Jefferson, any more than it is a fault in Kurt Vonnegut if he never really learned to use an iPod. My point is simply that fashions change, and it's interesting to note how we -- society, educators -- now reflexively lionize "reading", including the reading of novels, as a pure virtue. That Jefferson is simultaneously sainted as a model of intellectual probity by the same people is what makes the quote so entertaining.
Actually Jefferson was a smart cookie, and his criticisms, insofar as they were valid then, are just as valid now.