zork

Now that I've totally dropped the ball on our conversation...

I'm not sure what kind of evidence you want for the idea that language (e.g.) is a shared phenomenon. You're right - if the point of language is to get you to have the same inner experiences that I'm having, there's no *proof* that we can accomplish that. That's not what I meant. What I mean is that we all get together and manipulate symbols with each other in various interesting ways - and that, unless there simply is no external world, is obviously shared and raises no *special* problems of mentalism.

As far as general skepticism goes... there are a few elements to my anti-skeptical position:

1. Of course we have *evidence* of the external world's existence! I see things, touch them, eat them, encounter them in various ways. All of these seem like good evidence of their existence. Of course, also, I might be wrong - but that just means that I maybe can't 100% deductively prove that these things are out there, it doesn't mean that I don't have good evidence for them.

2. But: foundationalism is a suspect epistemological doctrine, anyway. Most general skepticism is founded on a kind of foundationalism that basically says that, if you are warranted in believing something, you need to be able to trace that belief back (found it upon) some 100% provable indubitable claim, or a claim that we know indubitably and non-inferentially, without needing any background knowledge (basically, Descartes' view). This runs us into a problem Sellars called 'the myth of the given,' however. Not everything is going to be traceable back to deductively provable claims (e.g., pure mathematics). So we're going to need something like indubitable non-inferential observation claims to found any knowledge whatsoever. But any conceptualized claim can't be completely independent of inferentially articulated background knowledge (I can't look at an apple and say, "oh, that's red" without knowing a lot of stuff about how to use 'red'), and an unconceptualized claim can't function in an inference (going from "the apple is red" to the "the apple is colored" is a good inference, but going from *look at apple* to "the apple is colored" simply isn't an inference at all). So it's not just that we may not have any of the requisite sorts of observations, they don't seem to be in-principle possible. That would seem to indicate that the problem isn't that we're missing something, but that we've misconceived how evidence is supposed to work.

3. What to replace it with? Contextualism. Unmotivated doubt is pathological. If I have decent evidence for something, I should only doubt it (beyond bare fallibilism, saying "I could, of course, be wrong") if I have some *reason* to. I have no reason to doubt that I am sitting in front of my computer right now. If I were to learn that I'd just been dosed with LSD, I would then have reason to doubt it, and would be justified in seeking further evidence, not taking the computer's existence for granted, etc. Similarly, this is why skepticism has trouble keeping most people up nights. We should accept bare fallibilism with respect to the external world, but most wholesale skeptical scenarios are implausible - that is, if the competing hypotheses for explaining why things seem the way the are are a) for the most part, they are the way they seem or b) an omnipotent demon is controlling my perceptions, a) wins. It's just good sense to believe the more likely explanation, or the one that fits better with your background theory.

That was horribly compressed. I hope it made some degree of sense...