Taking the Slippery Slope Seriously...

...At least seriously enough to show why those who invoke it can't be serious.

The other day a student of mine told me she'd been with a friend to a Young Republicans meeting. Since we'd recently been talking about same-sex marriage in class, when the topic came up at the meeting she asked the speaker about the propriety of invoking religious arguments when the topic is civil marriage.

The speaker responded with the famed slippery slope argument: If we let gays get married, what's to stop Farmer Joe from marrying his goat?

Apparently, he conceded that this wasn't likely to happen "here in Oklahoma." But still, he threw it out there as an "extreme" that legalizing same-sex marriage would open the door to.

My student was a bit astonished, probably because the slippery slope argument was one of the more preposterous challenges to marriage equality that we'd talked about in class. It was an argument I'd picked apart with some care. Once you've actually done that--taken the time to walk through the process of picking apart the logic (or lack thereof) of the slippery slope argument--it's very hard to take seriously anyone who brings it up in all earnestness.

But not everyone has actually walked through the argument in that careful way. It's not surprising. More often than not in public dialogue today, when someone brings up the slippery slope argument critics respond with rolling eyes, ridicule, and one-liners.

I understand the impulse. I do. I even think there's a place for it. But there's also a place for taking the argument seriously enough to demonstrate why it doesn't work--why it's failure is not just a matter of opinion but a fact about the argument.

Most critics don't take the time to show this. Consider the following rebuttal from Bill Maher:



Now he makes a significant point here: As a matter of history, instances of extending rights to people traditionally excluded from them have not, inevitably, led to animals acquiring those same rights.

But there are problems. First of all, there are those (such as Peter Singer) who draw parallels between the pursuit of human equality and the pursuit of animal equality, and attempt to make the case for animal equality on those grounds. They don't support voting rights for dogs--for good reasons. But if you're not thinking clearly about those reasons, you might get caught up in confusions that undercut what Maher is trying to say.

The deeper problem with Bill Maher’s comment here is that some people will say, “Yeah, but same-sex marriage is different from voting rights for women.” They’re wrong about that, but Maher’s comment doesn’t show them why. And until you clearly show why, those who persist in making the slippery slope argument can do so without its unsoundness being plain for all reasonable people to see.

So, consider this post an effort to show why same-sex marriage is no more likely to open the door to inter-species nuptials than women's suffrage was prone to culminate in voting rights for lemurs. If anyone doesn't already see why this is so, feel free to refer them here.

When I talk about the slippery slope argument against same-sex marraige with my intro-level ethics students, I treat it as if it were a serious objection. This affords me the opportunity to make some general points about when slippery-slope arguments are valid and when they're not.

I explain it as follows: A "slippery slope" from one public policy decision to some extreme outcome exists if and only if your reasons for making the policy decision, were they accepted as sufficient, would also have to be regarded as sufficient for allowing the extreme outcome. So, you need to ask about the REASONS why we would make the policy decision in question. If the reasons for extending voting rights to women are also adequate reasons for extending those same rights to hamsters and lemurs and squid, then a slippery slope exists. If the reasons don't extend from women's suffrage to hamster suffrage in this way, then no slippery slope exists.

So: in the case of extending voting rights to women, what was the reason? It was that women have both an interest in democratic participation through voting and a capacity to participate in this way. As such, their disenfranchisement is legal discrimination. Not so for hamsters.

Likewise, gays and lesbian have both an interest in having their intimate life-partnerships legally recognized and supported by the battery of rights that go with civil marriage, and they have the capacity to enter into such legal partnerships. As such, their exclusion from marriage is legal discrimination. Not so for Farmer Joe and his goat.

This is the short version. But a more detailed debunking of the slippery-slope argument is possible...and, for reasons I'll get to at the end, I think it's worth it.

Equality under the law is a crucially important secular value in a liberal democracy. Thus, any unequal treatment under the law requires a compelling justification—of the sort that obtains in the case of, say, denying drivers’ licenses to the blind. The justification cannot be a purely sectarian religious one (such as, “My faith teaches me that women are subordinate to men and should defer to men in important decision-making, and so shouldn't vote”). That would allow one religion, not shared by all in society, to trump a central, shared secular value (namely the desire everyone has to be treated equally under the law). Such religious trumping of secular values would mean the state is adopting for policy purposes a particular religion’s beliefs, and it would involve making all citizens subject to the implications of this one religion’s teachings. As such, it would violate both separation of church and state and freedom of religion.

Put simply, women were given the right to vote because failure to give them this right amounted to discrimination under the law, and we couldn't see any compelling secular justification for such discrimination.

But what about hamsters? Hamsters have no interest at all in democratic participation through voting...and are wholly incapable of it. Give them the vote, and they'll keep running in the hamster wheel and chewing all night long on the bars of their cage. And they will never vote. Ever. Although some hamster owners might see the opportunity for voter fraud by registering their hamsters and "helping" them cast their ballots.

In short, denying voting rights to hamsters does not deny them anything they could actually use. The case for legal discrimination doesn't even get off the ground. You're not the victim of discrimination when the law refuses to give you what the law cannot possibly give you.

The same-sex marriage case is completely parallel to this. In the case of extending civil marriage rights to same-sex couples, what’s the reason? The reason begins with an understanding of what, from the standpoint of the state that confers civil marriages, the marital relationship is. The state sees marriage as an intimate association defined in terms of life-partnership, a partnership usually formed based on love and characterized by mutuality, support in life's activities (which may or may not involve shared responsibility in child-rearing), shared decision-making, help in times of trouble, etc. The range of legal rights conferred on married couples reflect this understanding of the marital contract as an intimate life-partnership.

So here's the problem. Restricting civil marriage to straight couples means that legal recognition of one's intimate, loving life-partnership (and the rights that go with that recognition) is made available to persons with a heterosexual orientation but denied to those with a homosexual one. This is legal discrimination (and if you think Michele Bachmann's rebuttal to this has any force, see here). Legal discrimination must have an adequate justification—which can’t be a sectarian religious one.

The reason why more and more people are arguing for extending civil marriage rights to gays and lesbians is because not doing so is legal discrimination, and because they can't see any compelling secular justification for inequality under the law in this case.

But what about Farmer Joe and his goat? They're not being denied anything by being deprived the right to marry, because they cannot form an intimate life-partnership in any event. A "partnership" in the human sense involves a deliberate mutual decision to share in the challenges and opportunities of life, to make important choices together, to share responsibilities, etc. My friends John and David are fully capable of forming such a partnership (although Rick Santorum seems committed to denying this for reasons that are more than dubious and involve waving napkins around). My friends Pat and Diana have a long-standing partnership that would be a model for married couples everywhere.

Joe and his goat, not so much.

Thus, Joe and his goat aren't being denied legal recognition of an intimate life partnership, because they can't have such a thing in the first place. The case for legal discrimination against Joe and his goat doesn't even get off the ground--and this is clear even if we never even address the fact that homosexuality as an orientation is real, whereas the hypothesis of a hetero-species orientation (such that some people--and goats, I suppose--are only capable of forming and sustaining romantic relationships with animals of species other than their own) is dubious at best.

Even were we to somehow stumble erroneously into the view that it is legal discrimination to deny Joe and his goat a wedding licence, there are obvious secular justifications for such "discrimination" that simply don't come up in the case of the actual discrimination that is really taking place when same-sex couples are denied civil marriage. The state is in the marriage business in part (as Jonathan Rauch has convincingly argued) to help provide "default support persons" for members of society--someone whose job it is to be there to help you through the hard times. That's a key reason why the government happily issues marriage licenses to elderly couples who meet at the church bake sale, even though there is no prospect of children. It's a good reason for the state to issue marriage licenses to gay couples, too.

But the goat isn't going to provide Farmer Joe with any such support. I suppose Joe could eat the goat if he falls on hard times, but a marriage license won't help him do that.

It may seem as if, by taking this argument as seriously as I have, I've been beating a dead horse. Or a dead goat.

And I have. The metaphorical goat is, after all, dead. But apparently some people haven't noticed yet. Maybe they think it's just sleeping or something. In such cases, it may help to wallop the corpse.

And sometimes walloping the corpse makes the situation clear in advance, such that a smooth-talker making the case that the goat is alive won't be persuasive.

"I've seen the goat. It didn't budge when Uncle Roy whacked it. Trust me, it's dead."

UPDATE: In response to comments asking about less "extreme" slippery slopes, I've written a follow-up post that applies the same strategy of thinking to the purported slippery slope from same-sex marriage to group marriages. Check it out here.