Friday, December 14, 2012

[PL 211] A slippery slope to the absurd

It looks like Justice Antonin Scalia doesn't know the difference between reductio ad absurdum and slippery slope arguments.

Can you help him out?


  1. I don't think Scalia made the mistake you're attributing to him. Stewart didn't supply the full quote. You can get a more representative version of the quote here:

    The reductio, was as follows:
    1. It is inappropriate for society to express moral animus against behavior that is not constitutionally protected, just because society finds it morally objectionable.
    2. Laws against murder (or bestiality, etc.) express moral animus against murder (or beastiality)
    3. Laws against murder (or bestiality) are illegitimate.

    Now I think you could retort that laws against murder are not justified merely as expressions of moral outrage, but merely by appeal to a harm principle (which they meet and anti-sodomy laws do not), but:
    1. That argument is a moral argument; not a constitutional argument.
    2. That point has no bearing on the validity of the reductio. It would just be denying that the conclusion is in fact absurd. I think many (most?) would actually agree with Scalia on this one (that moral animus is a legitimate motivation for a law).

    1. Stewart misquoted (or quoted out of context) Scalia? Unbelievable! What’s the world coming too when you cannot trust a comedy show to get the facts straight?

      Seriously, though, I think that there are a few things that are not clear about Scalia’s argument. First, I don’t think that Hosie was trying to defend (or even suggest) something like (1) in your reconstruction of Scalia’s argument. Rather, Hosie was probably just calling on Scalia to *reevaluate* things he wrote in 1996 and 2003, given that nowadays few Americans seem to share Scalia’s moral feelings about homosexuality (

      Second, suppose, for the sake of argument, that many Americans still have the kind of moral disgust toward homosexuality that Scalia has. The slippery-slope part of Scalia’s argument (i.e., “If we cannot have moral feelings against homosexuality, can we have it against murder? Can we have it against these other things?”) is supposed to show that no meaningful distinction can be drawn between moral outrage in response to gay sex and moral outrage in response to murder; otherwise, the “reductio” doesn’t go through. But this part of the argument is so confused. Is Scalia trying to say that no meaningful distinction can be drawn between having moral feelings against homosexuality and having moral feelings against murder? Or is he trying to say that no meaningful distinction can be drawn between expressing moral outrage in the face of gay sex and expressing moral outrage in the face of murder? Or is it that if moral feelings against homosexuality are inappropriate, then moral feelings against murder are inappropriate, too?

  2. You're probably correct that Hosie didn't intend (1). But Scalia did. Scalia was asked if he regrets what he wrote in Romer and Lawrence. His claim there is that moral outrage is a legitimate (sufficient?) ground for criminalization. Moral outrage is a social fact about a society. Scalia is claiming that no constitutional right is infringed by society's taking away your rights to life/liberty/property if you've been found guilty of committing a crime society finds morally outrageous (and which wasn't a protected constitutional right), subject to due process of law, etc.
    Scalia's argument could equally be put thus: if it's ok to criminalize murder on the grounds of moral outrage, then it's ok to criminalize gay sex on those grounds. Now that claim can translate into Scalia's reductio (If it's not ok to ban gay sex, then it's not ok to ban murder [reductio!]) or, alternatively, to a reductio against the expressivist theory of punishment in the first place (if it's ok to ban murder on expressivist grounds, then it's ok to ban benign things like gay sex [reductio!]). Either way, though, the formal structure of the argument is a reductio.
    My point here isn't to defend the expressivist theory, Scalia's or Texas' feelings about gay sex, etc. It's just to point out that he's not conflating a slippery slope argument with a reductio.
    Now, I'd agree with you that the moral outrage expressed towards murder is different (or at least differently justified) from the moral outrage some might have towards gay sex. You might think that this shows that the reductio fails because it's not picking out the correct principle - but still doesn't show the argument isn't properly classified as a reductio.

    1. Your last sentence raises interesting questions about reductio arguments. Suppose that you’re right about Scalia’s reductio, so his argument is supposed to be something like “If it's not ok to ban gay sex, then it's not ok to ban murder.” Now, it seems that this claim doesn’t strike Stewart (and/or his writers), and perhaps Hosie, too, as absurd at all. That is, it seems that it doesn’t strike them as absurd to say that it’s ok to ban murder on “moral animus” grounds but it’s not ok to ban gay sex on “moral animus” grounds. Now, the interesting question is this: If you make a reductio against an opponent’s position, and you take your reductio to lead to an absurd consequence, which is supposed to show that your opponent’s position must be rejected, but your opponent doesn’t think that the consequence is absurd at all, is it still correct to classify your argument as a reductio?

      A related question, stemming from The Daily Show clip, is this: If you think that your opponent’s argument doesn’t make sense as a reductio (since you don’t think it leads to an absurd consequence), does charity dictate that you ought to interpret your opponent’s argument in the best light possible (e.g., as a slippery-slope argument) even if your opponent claims that his/her argument was meant to be a reductio?


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