Isn't it about limiting the chances of genetic conditions occuring?
Given that a deformity or genetic illness is something like 16 times more likely if the parents share similar genes?
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chenobble rocking his explorer beard on, Fri 11 Jan 2008, 14:24,
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Illness is more likely, but still not likely after just one generation. And, given the level of knowledge about genetics when the taboo grew up - none at all - it's difficult to explain that way.
Nor would the welfare of the child explain it. A child born to siblings would still, almost certainly, have a life worth living, and so benefit from being born.
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Enzyme is powered by sunlight, Fri 11 Jan 2008, 15:06,
Reply)