This was my argument in another thread.
Incest can give birth to defect children, yes, but so can sex with
an AIDS partner. Incest can lead to defect babies, but note that
incest is not the act of creating babies.
Like the reasoning made by homosexuals, a sexual relationship is a
private affair between two people. Why should the law be bothered
by it?
The point is that throwing away any religious argument, there isn't
any compelling reason to ban incest.
