Out with the old …

… skeptical arguments.



A new paper of mine, “Skeptical Appeal: The Source-Content Bias” (forthcoming in Cognitive Science), uncovers a subtle mechanism that triggers knowledge-denial and contributes to the appeal of classic skeptical arguments.

The mechanism is an interaction between two factors. First, people evaluate inferential belief more harshly than perceptual belief. Second, people evaluate inferential belief more harshly when its content is negative (i.e. that something is not the case) than when it’s positive (i.e. that something is the case). That is, our cognitive evaluations are biased against this specific combination of source and content.

The skeptic exploits, perhaps unwittingly, the source-content bias. It just so happens that certain skeptical arguments tend to focus our attention on negative inferential beliefs, and we are especially prone to doubt that such beliefs count as knowledge.

Philosophers have long appreciated that research into features of language might help shed light on skeptical appeal (e.g. Cohen/DeRose/Lewis style contextualism, or invariantist proposals that invoke pragmatics). My New Year’s resolution: to keep firmly in mind that philosophically-informed research into features of our psychology can be equally helpful.

Who’ll join me?


Out with the old … — 2 Comments

  1. wicked cool, john! one question (in advance of having read the paper): do you take yourself to be in a position to argue that the effect sizes here are sufficient to totally explain away the intuitions at the heart of these skeptical arguments? How easily could a proponent of these skeptical intuitions respond by saying that, while these effects may make these intuitions, in some sense, even more compelling than they should be, nonetheless the intuitions are sufficiently strong _even factoring in these effects_ that we need to take skepticism seriously?

  2. Thanks, Jonathan!

    That’s a great question. For the studies reported in this paper, the 95% CI for the odds ratio for the interaction is ~ 2 to 5, which is small-to-medium. But these were earlier studies in a line of research that has continued. As things progressed, I discovered that slightly better procedures and dependent measures could detect the interaction with much greater sensitivity. I’ve seen the likeliest odds ratio for the interaction reach 35, with an upper limit of the 95% CI reaching 350!!

    If I had to make an educated guess, I’d say that the true odds ratio for the interaction is 10-15, which is very large. And, in this entire line of research, I’ve observed people deny knowledge at significant rates *only* in negative inferential conditions.

    So, yes, I think that this bias goes a very long way toward explaining the skeptical intuitions at the heart of these arguments. Given the current evidence, the skeptic could not really make a plausible case that there’s something serious left over once these effects are taken into account.

    If you’re interested in seeing the paper reporting the more recent experiments, just email me and I’d be happy to share.

    Incidentally, I do still think that some pragmatic aspects of knowledge attributions help explain some of the motivation for skepticism. (I discuss one such aspect in my paper, “Linguistic Intuitions in Context.”)

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