Opiniatrety

More On Ecumenicism

I'd like to add a bit to my entry on ecumenicism in epistemology and the metatheory/normative theory distinction. Hopefully this will be a bit clearer (to those who made it through the previous sentence).

I argued that Newcomb's problem and the problem of what justification is are different enough that ecumenicism makes sense for justification but not for Newcomb. Newcomb's problem is a normative problem; it asks the question "What to do in this case?" The answer is an action--the subject has to take one or both boxes. The definition of justification is metatheoretical; it asks the question "What property should we use 'justification' for?" The answer is a conceptual definition, and we can simply decide to define two senses of 'justification', an internalist and an externalist one.

But here's an objection: Newcomb's problem is meant to illuminate theories of rationality. We're supposed to conclude that it's rational to maximize expected utility, or that it's rational to act according to causal decision theory. Isn't this a metatheoretical question about the use of 'rationality'? Shouldn't it be analogous to the metatheoretical question about 'justification'?

One answer may be--to say "Action A is rational" is to say "Do A." So the metatheoretical question turns into a normative one. But then you can (so the objection goes) raise the same question about belief--to say "Belief P is justified" is to say "Believe P." If that's true, then you can't be ecumenical about justification any more than about rationality--you'll be counselling someone both to believe and not believe something.

Two responses to the objection:

(1) [This depends on a difference between theoretical and practical reasoning.] "Believe P" isn't actually advice, because we can't believe or not believe at will. This means that any counsel about what to believe is moot. We can, on the one hand, advise people about what actions to perform to get their beliefs in working order, and, on the other hand, evaluate the beliefs they do have according to various good-making properties.

Epistemic justification addresses the other hand only; the one hand is a kind of practical rationality about achieving epistemic ends. So, anyway, I claim--there's a kind of purely epistemic justification that doesn't allow that beliefs can be justified because the believer is incapable of believing otherwise. Then the believer may be free from blame, but the belief can be criticized. There's nothing to stop us from using two different criteria to evaluate the belief. In contrast, in Newcomb's problem you're actually looking for practical advice, and there's no room for criticizing the action without criticizing the actor who chose it.

(2) In Newcomb's problem the actor has full information (well, except about what's in the opaque box--in most versions). There's a debate over rationality that's more analogous to the internalism/externalism debate: Should you adopt the course of action that actually will have the best consequences, or the course of action that you expect to have the best consequences? (That question, I admit, carries a presupposition that not everyone will grant.)

There are those--I think Parfit does this--who say that you have reason to do something if it would have a good consequence, even if you have no way of knowing that that good consequence will come to pass. But I don't think most people will say that and deny that there is some sense of rationality in which it is practically rational to do what you have epistemic reasons to think you have practical reason to do. For instance, Keith DeRose says that we don't blame someone for violating the knowledge norm of assertion when they have reason to think that they knew what they said, calling this a secondary norm that derives from more general norms.

Let's transfer this to the epistemic case, supposing that you could choose your beliefs at will. Which beliefs should you choose? On externalism, those beliefs that are justified by the externalist criterion of justification. What if you choose a belief that is internalism-justified but not externalism-justified? Well, then you haven't believed what you have most reason to believe. But you had no way of telling what you did have most reason to believe. In fact, on the information you had, it could not but seem that what you had most reason to believe was what you did believe. So it seems as though the externalist ought to say, along with the externalist about practical reason, that there's a sense in which you were rational to believe what you did, even though you didn't believe what was justified.

In short: In some sense, the externalist should admit that it's OK to believe what's internal-justified. The advice "Believe what's external-justified!" is not always one that can be followed, no matter how smart you are, if you don't have enough information. Then the best you can do toward following that advice will be to believe what's internal-justified.

This argument puts pressure on the externalist to be ecumenical, but I don't think there's any similar pressure on the internalist. The internalist should acknowledge that there is more than one way to evaluate beliefs--internalist justification is the best attempt a goal that's partly determined by externalities. But I think that goal is truth. Externalist justification is an uneasy compromise between truth, which we actually want, and internalist justification, which is the best we can do.

Posted by Matt Weiner at April 19, 2004 01:24 PM