Now for the slippery slope arguments—those rationally indefensible, but emotionally satisfying predictions of what "something" is going to lead to. The “somethings,” of course, are the two recent Supreme Court rulings on same-sex marriage. The “what they are going to lead to-s” are getting more interesting by the hour. The following five potential world-ending catastrophes have all been culled from statements of politicians and pundits over the last few weeks. From what I can tell, they represent something like a consent-agenda for the coming parade of horribles.

1. POLYGAMY

There are a few things wrong with the theory that support for same-sex marriage will lead inexorably to the United States of Big Love and Sister Wives. In the first place, most polygamists in the United States do not seek, or even particularly want, civil marriages. They marry by their own authority, which they see as both necessary and sufficient.

What polygamists tend to seek, politically, is an end to “unlawful cohabitation” laws—those 19th century statutes created to tame Mitt Romney’s (and my own) Mormon polygamist forbearers. These laws make it a crime to live with somebody of the opposite sex to whom you are not married or otherwise related. Most jurisdictions already consider these laws unenforceable, which is why polygamists who are not welfare cheats or child molesters tend to be allowed to go about their business in peace.

But an even more important reason that the courts will never force society to give traditional marriage rights to polygamous families is that it would be impossible to do so. Changing the gender assumptions of the marriage contract doesn’t change the legal nature of that contract at all. Changing the number assumption, however, changes that legal nature beyond recognition—as most of the legal relationships that married people automatically enter into (property division, powers of attorney, child custody, tax status, etc.) do not even make sense for numbers greater than two. If a man on life support has three wives, only one of them can have final say about whether or not to pull the plug.

2. INTERSPECIES MARRIAGE

Both Rand Paul and Glenn Beck apparently believe that this is coming next. It is not. Anybody who seriously suggests that same-sex marriage will lead to humans marrying animals seriously misunderstands the nature of contracts generally. Marriage is a contract, and animals cannot enter into contracts.

There are also those (Pat Robertson for example) who say that gay marriage will lead to bestiality, or sexual relations between humans and animals. But they are too late. Eighteen jurisdictions in the United States alredy permit human beings to have sexual relationships with animals. That is four more jurisdictions than allow same sex-marriage.  And five states--Texas, Georgia, Kentucky, Virginia, and Ohio--that are constitutionally required to void a legal same-sex marriage performed in another state are completely OK with a human being (of either gender) having sex with a poodle.

3. PEDOPHILIA

Pedophilia is a crime in which a minor who is unable to give consent is victimized by a horrible human being. It has nothing to do with a contract between two mutually consenting adults. Period.

4. INCESTThe spectre of incest is often included with pedophilia and polygamy as one of the things that we open ourselves up to when abandon the traditional definition of marriage. But the underlying legal arguments are very different. Laws forbidding close relatives (brothers and sisters, for example) from marrying each other are based, not just on social taboos, but on actual scientific evidence that the natural children of such marriages are at a much higher risk for birth defects. The fate of natural children is the one thing that we don’t actually have to worry about with same-sex marriages.

One area where same sex marriages really might set a precedent is the fuzzy legal arena of cousin marriages. The children of first cousins tend not to have any elevated risk for birth defects, but many states still prohibit first cousins from getting married. Twenty-one states permit first cousins to marry, however, and, in almost every case, these marriages are legal throughout the country. Eight states, however, still have laws on the books that would void first-cousin marriages performed in other jurisdictions. These laws have never been tested in federal courts (largely because they are almost never enforced). But I suspect that their fate will be bound up with the coming debates about same-sex marriage policies in the states.

“The overturning of unenforced cousin-marriage recognition laws” is not nearly as horrifying as “polygamy with underage goats." But I will concede that, in the former case but not the latter, the slope will probably ending up slipping there.

5. THE END OF THE WORLD

As I understand the argument, it goes something like this: For the last 2,000 years or so, we have defined marriage as a relationship between one man and one woman, which (the entire Old Testament notwithstanding) also happens to be how God defines it. Now that we are changing that definition, God is probably going to get really mad and destroy us.

There is no way to argue with such an assertion, I suppose. God will do what God will do, and he has not chosen to take me into his confidence. It is worth pointing out, however, that God has tolerated a lot of pretty awful stuff in the last two thousand years—much of which has been "legal" for those doing the horrible things. Whole countries have been wiped out and put to the sword, an entire hemisphere of people was depopulated by European conquerors, millions of people were stolen from their homes and sold into slavery, 6 million people were gassed in ovens, millions of peasants were intentionally starved to death by centralized agricultural policies, thousands of Japanese and Korean women were kidnapped and sent to be raped by soldiers as “comfort women.” And so on.

I am going to be really surprised if a procedural ruling about who has standing to sue on behalf of the state of California turns out to be God’s deal breaker.