William Saletan argues in Slate Magazine against the fake “slippery slope” argument used by delusional conservatives who say legalizing same-sex marriage will lead to the legalization of incest.

Morally, the family-structure argument captures our central intuition about incest: It confuses relationships. Constitutionally, this argument provides a rational basis for laws against incest. But it doesn’t provide a rational basis for laws against homosexuality. In fact, it supports the case for same-sex marriage.

When a young man falls in love with another man, no family is destroyed. Homosexuality is largely immutable, as the chronic failure of “ex-gay” ministries attests. So if you forbid sex between these two men, neither of them is likely to form a happy, faithful heterosexual family. The best way to help them form a stable family is to encourage them to marry each other.

Very well said. The idea that legalization of same-sex marriage leads to anything except same-sex marriages is an idiotic canard used to fool the easily gullible — such as Porno Pete’s five followers. Furthermore, there is actual proof that the argument is bogus. In countries and states where marriage equality exists, it has not affected laws on incest.

Case closed.