When parents take measures to select for beneficial genetic traits in their children (e.g., by selecting MENSA members as sperm donors), who benefits? I take it that the intuition is that the children benefit. There's something weird about this idea, however. It's not as though we are conferring intelligence or good looks on a child who would otherwise be ordinary; rather, we're trying to ensure that the ordinary child never comes into existence in the first place.

Your last sentence is right: It's not true that in the case you have in mind the parents confer a benefit on child that would otherwise lack it. You're right also that it is a bit strange to suppose that children benefit from this. On the other hand, one might argue that this practice benefits society at large by increasing the overall representation of intelligence. (Whether increasing the overall level of intelligence in the population will benefit it, is an empirical question to which I doubt we have an answer.) Or one might hold that it benefits the parent or parents by increasing their chances of having high-achieving children. (Whether having smarter children in general makes parents happier is also an empirical question, and I also doubt that we know how to answer it at this point.)

You might enjoy pursuing these issues a bit further with Jonathan Glover's new book, _Choosing Children: Genes, Disability and Design_, forthcoming in early 2008 with Oxford University Press. Glover is an excellent writer and a very fine philosopher.

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