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Skepticism About Skepticism

I Doubt It

My last article discussed the following propositions: the 'Moorean proposition' and the 'skeptical proposition,' named in honor of G.E. Moore, the Cambridge philosopher who fathered the standard response to skepticism.¹

The Moorean Proposition
You know that you're sitting at a computer right now.

The Skeptical Proposition
You don't know that you're not trapped in the Matrix, being deceived to think you're sitting at a computer right now.

The Moorean proposition is either true or false; either you do know you're sitting at a computer right now, or you don't know you're sitting at a computer right now. Likewise, the skeptical proposition is either true or it's false; either you don't know you're not in the Matrix right now, or you do know that you're not in the Matrix right now. Given the closure principle, however, and the fact that you know you're only sitting at a computer right now if you're not trapped in the Matrix,² the skeptical and Moorean proposition are mutually exclusive. This means that the truth of one entails the falsehood of the other. So right now, as you read this, you're in one of the following situations.

The Moorean Situation
You know you're sitting at a computer; consequently, you also know you're not trapped in the Matrix.

The Skeptical Situation
You don't know you're not trapped in the Matrix; consequently, you don't know you're sitting at a computer.

So, which is it? Most people would be inclined to say you're in the Moorean situation. The skeptic, of course, would disagree. He'd say that, because you can't rule out the possibility that you're trapped in the Matrix, you don't know you're not. Thus you're in the skeptical situation. Is the skeptic right?

I Still Doubt It

I don't think so. In fact, I think there are good reasons to be skeptical about skepticism.

The skeptic, recall, argues as follows:

(1) If propositions A and B are mutually exclusive, you're aware that A and B are mutually exclusive, and you can't rule out the possibility that B's the case, then you can't (truthfully) claim to know that A's the case.

(2) The proposition that you're sitting at a computer and the proposition that you're trapped in the Matrix are mutually exclusive.

(3) You're aware that the proposition that you're sitting at a computer and the proposition that you're trapped in the Matrix are mutually exclusive.

(4) You can't rule out the possibility that you're trapped in the Matrix.

Therefore,

(5) You can't (truthfully) claim to know you're sitting at a computer.

This argument is clearly valid. If (1) through (4) are true, then (5) has to be true as well. Premises (2) and (3) are non-controversial. The propositions in question obviously are mutually exclusive, and you're well aware of this fact. So, if we're going to find fault with this argument, we'd better look at premises (1) and (4).

Oh Yeah. Prove it!

Taking them in turn, (1) seems true, too.

You think John owns a Rolex. You're friend points out that he just got back from Bangkok, where look-alike Rolexes are sold on the street for $10. You admit that you can't rule out the possibility that John's watch is a fake. It seems, then, that you don't really know John owns a Rolex.

You see a hawk perched in a dead tree and point it out to a friend, who responds, "Isn't that a falcon?" You realize you can't rule out the possibility that he's right. In this case, isn't it obvious that you don't really know it's a hawk?

If there's something wrong with the skeptic's argument, then, it looks like the problem's got to be in premise (4).

No, It's Not.

So why think (4) is true?

Again, you think John owns a Rolex. But now you think this because you're a trained Rolex technician, and you've done extensive work on his watch. Your friend points out that John travels to Bangkok every month, where look-alike Rolexes are sold on the street for $10. You respond, "I'm perfectly capable of identifying a Rolex when I see one, and I've seen John's watch up close. I know it's not a fake."

Or take the hawk scenario again. You're friend suggests that you're really looking at a falcon, but now you know hawks are the only birds in the world with the particular combination of beak, wings and legs you're presently observing. You respond, "I admit, I don't know anything about falcons. But I do know that bird's a hawk. If hawks and falcons are different kinds of birds (as you say they are), then I'm perfectly capable of ruling out the possibility that the bird we're looking at is a falcon. In fact, pick anything that's not a hawk and call it an X. Because I know that bird is a hawk, no matter what you've picked for X, I can rule out the possibility that that bird's an X."

These scenarios seem reasonable enough. If you're competent to judge whether or not the watch is a Rolex, then you're also competent to judge whether or not the watch is a fake Rolex. And if you know a hawk when you see one, you're in good position to rule out the possibility that any hawk you see isn't an X.

So, in response to premise (4), why can't you simply respond to the skeptic as follows?

"What do you mean I can't rule out the possibility that I'm trapped in the Matrix? If I'm sitting at a computer, then I'm not in the Matrix. I'm perfectly capable of determining whether or not I'm sitting at a computer, and this means I'm perfectly capable of determining whether or not I'm in the Matrix. As a matter of fact, I am sitting at a computer. It follows that I'm not trapped in the Matrix. So there you have it. I just ruled out the possibility that I'm trapped in the Matrix."³

At least one problem with premise (4), then, is this:

There seems to be no (non-question begging) reason for thinking you can't rule out the possibility that you're in the Matrix by simply noting that you're sitting at a computer. After all, from the fact that it's metaphysically possible that you're trapped in the Matrix (and therefore not sitting at a computer) it doesn't follow that it's at all likely that you're trapped in the Matrix. The skeptic has given you no reason whatever to think you're not sitting at a computer, and if you are sitting at a computer, then you're not in the Matrix.

No, It's Not!

But suppose the skeptic objects that there's something fishy about inferring that you're not trapped in the Matrix from the fact that you're sitting at a computer right now, since the whole point of raising the Matrix possibility was to cast doubt on your belief that you're sitting at a computer.

I think this objection amounts to little more than the complaint that you're unwilling to play the skeptic's game, but, for the fun of it, let's pretend the skeptic's got a point. Must we now concede premise (4)?

Again, I don't think so. Consider the following scenarios:

The whole world's conspiring against you. To your face, people treat you pretty much the way they treat everyone else. But when you're not looking (or recording things with a video camera), pretty much everyone on earth moons you. Those who don't moon you usually flip you off. If you ask, everyone will deny they do this. But of course, this is all part of the conspiracy.

NASA's conspiring against the whole world. Our space program is a complete hoax. The rockets they blast off are really just elaborate fireworks, and all of the people apparently involved are just actors. The moon landing was filmed in Hollywood. Everybody with access to this information is paid by NASA to lie. Whenever anybody new finds out, they're either bribed to keep quiet or suddenly involved in a fatal accident.

You're conspiring against yourself. Whenever you're alone, you sing Britney Spears songs at the top of your lungs, then head to an expensive psychiatrist who hypnotizes you. The hypnosis not only makes you forget that that's what you've been up to, it has you believe you're not the sort of person who'd ever do such a thing in the first place.

Now, I'll bet you not only don't believe anything in the above paragraphs, I'll bet you believe everything they say is completely false. The interesting thing is, you have absolutely no evidence for the falsehood of any of their claims. Instead, they simply strike you as absurd, and this is why you reject them.

On my view, you're entirely rational to do so. You can't rule out these scenarios on the basis of any evidence, but you can rule them out as inherently absurd. You'd discredit yourself by taking them at all seriously, and this fact counts decisively against them.

The same goes, I think, for the Matrix scenario. Even if you can't rule out the possibility that you're in the Matrix by pointing out that you're sitting in front of a computer, you don't need to. While it's metaphysically possible that you're in the Matrix, the suggestion that you're actually in the Matrix is absurd, and this is sufficient for knowledge that you're not in the Matrix.

So, most of us believe you actually do know lots of things, including that you're sitting at a computer right now. The skeptic thinks otherwise, but his argument depends on premise (4), above. And as we've seen, there's good reason to be skeptical about premise (4). Embracing the skeptic's argument, then, seems to require a certain amount of dogmatism. Since dogmatism is an intellectual vice, the intellectually virtuous course requires skepticism about skepticism.

See. I Told You

We started this series with the observation that, if the skeptic is right, then knowledge is impossible — in which case knowledge of God is impossible. This raised an important question: If we don't have a response to the skeptic, then what business do we have telling people they ought to believe in God? After all, if we can't defend the pedestrian claim that we know we're sitting at computers right now, how on earth can we defend our knowledge claims about the Christian faith?

C O F F E E  S H O P

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Do you agree with Blake? Do we have reason to doubt the skeptic?

Join the discussion!

What we've seen in this article is that skepticism isn't much of a threat — to the Christian faith or anything else we might believe. This is because skepticism takes care of itself. Sure, there's reason to be skeptical of the knowledge claims people often make. But there's a lot more reason to be skeptical of skepticism itself.