So, here’s what I take to be the canonical presentation of Ginet’s famous barn example, from Goldman’s “Discrimination and Perceptual Knowledge,” (JP, 1976), pp. 772-3, with two slight modifications: 1) I’m not able to produce the various funny little marks on the words “papier-mache” and “facades” 2) I’m bolding one phrase that will be important to the discussion (Goldman italicizes two instances of the word “knows”; since this blog seems to italicize everything that’s in block quotes, I’ll indicate Goldman’s emphasis by also bolding those instances of “knows”):
Consider the following example. Henry is driving in the countryside with his son. For the boy’s edification Henry identifies various objects on the landscape as they come into view. “That’s a cow,” says Henry, “That’s a tractor,” “That’s a silo,” “That’s a barn,” etc. Henry has no doubt about the identity of these objects; in particular, he has no doubt that the last-mentioned object is a barn, which indeed it is. Each of the identified objects has features characteristic of its type. Moreover, each object is fully in view, Henry has excellent eyesight, and he has enough time to look at them reasonably carefully, since there is little traffic to distract him.
Given this information, would we say that Henry knows that the object is a barn? Most of us would have little hesitation in saying this, so long as we were not in a certain philosophical frame of mind. Contrast our inclination here with the inclination we would have if we were given some additional information. Suppose we are told that, unknown to Henry, the district he has just entered is full of papier-mache facsimiles of barns. These facsimiles look from the road exactly like barns, but are really just facades, without back walls or interiors, quite incapable of being used as barns. They are so cleverly constructed that travelers invariably mistake them for barns. Having just entered the district, Henry has not encountered any facsimiles; the object he sees is a genuine barn. But if the object on that site were a facsimile, Henry would mistake it for a barn. Given this new information, we would be strongly inclined to withdraw the claim that Henry knows the object is a barn.
It’s never been that clear to me that Henry doesn’t know that the object is a barn. Well, I don’t know about “never”: For a while, I at least thought it was clear to me that Henry didn’t know: Perhaps moved by the apparently authoritative judgments of others, like Goldman, after I encountered the example, I rather uncritically joined the consensus that Henry didn’t know, and was happy for a few years to, for instance, accept arguments based on the premise that Henry doesn’t know in the example. However, when Ruth Millikan first confronted me with skepticism about that judgment, I had to admit that it really was not all that clearly correct. (See pp. 329-30 of Millikan’s “Naturalist Reflections on Knowledge,” Pacific Philosophical Quarterly, 1984. I didn’t encounter Millikan’s skepticism until she confronted me with it in person a few later, early in 1990, at which time she referred me to her paper.) Key to Millikan’s doubt here is the fact that Henry has not encountered any of the fake barns. Though I was — and still am –personally inclined to judge that Henry doesn’t know in that case, I became — and remain — skeptical enough that I no longer took the judgment to be clearly enough correct for it to be useable as the premise of a good argument.
I recently e-sent a draft of a book I’ve been working on out to several philosophers. In it, I relate the skepticism explained above. Interestingly, several epistemologists have taken note of that, and have written back, saying that they too didn’t share this intuition, and that they’re glad to see they have company. Perhaps there are others who might join our skeptical cohort? (Or is it an anti-skeptical cohort? We’re skeptical of the commonly assumed “intuition,” but since the intuition we are skeptical of is itself a skeptical intuition (to the effect that Henry doesn’t know), we’re in a sense non-skeptical.)
Fortunately, the purpose for which I was using the example in my discussion with Millikan was served just as well by an easy modification of the example, so I modified it, and have since often used the modified version. (I believe the first times I used such a modification in published papers were in 1996: I used this modification of the barn case in my “Relevant Alternatives and the Content of Knowledge Attributions” (PPR, ’96), and I used a similarly modified version of Dretske’s zebras example in my Encyclopedia of Philosophy (’96 Supplement) on “Relevant Alternatives.”* I just don’t know if others have used such cases (it’s a fairly obvious move to make), but would be happy to learn.)
(*Update 11/25/09: I’ve just discovered that I used such a modified version of the case in my 1995 “Solving the Skeptical Problem” (p. 30).)
So, Suppose Henry has encountered many of the convincing fakes — say, 19 of them — and has been convinced by these convincing fakes: he has confidently, but mistakenly, taken all of the fake barns he’s encountered to be barns. Now he’s encountering the only real barn in the district. He again confidently takes the object to be a barn, but from Henry’s point of view, there’s nothing special about this case: He’s no more confident about this identification than he was about all the others. But this time, he’s right –he’s 1-for-20 in his recent barn judgments. Does he know that the object is a barn? Here, I’m fairly confident that Henry doesn’t know. If you’re still not sure, we can try other modifications. For instance, we can suppose that Henry goes on to encounter 20 more fakes, and gets completely fooled 20 more times. Now he’s 1-for-40, and his one “hit” among many “misses” is right in the middle of a sea of errors. If you’re still not solidly intuiting that 1-for-40 Henry doesn’t know, there are still further changes we could try, but you’re probably beyond the reach of my help.
(You can similarly modify Dretske’s zebra case so that the subject actually has encountered, and has been fooled by, several cleverly painted mules that the zoo is using in the midst of a zebra shortage in a successful attempt to fool the zoo-going public, but is now encountering the only real zebra in the zoo.)
Why is the case typically presented with the feature that Henry hasn’t encountered any of the fakes? It seems that Goldman’s main use of the example — to motivate the relevant alternatives account of knowledge — would be well-served by the modified example, where intuitions against knowledge are stronger. For when we compare the modified example with a normal case, in which all the barn-looking objects in the area (including the ones Henry has encountered) have actually been barns, we find that Henry cannot rule out the convincing-fake alternative in either scenario, but that his inability to rule that alternative out seems to block his knowledge only in the case in which there are fakes. So the actual presence of the fakes, together perhaps with Henry’s having encountered & been fooled by them, seems to make the alternative that what he is now seeing is a fake relevant.
But one of the points that Goldman goes on to make is that Henry’s evidence is the same whether or not the other object that look like barns in the area really are barns, and I speculate that he didn’t want to jeopardize that claim. (Much depends here on how exactly one construes the notion of evidence, but even if the fakes look exactly like real barns from the road, there are ways of construing evidence such that one is getting different evidence, depending on the nature of what one is actually seeing.) So, since he thought the intuition that Henry doesn’t know was solid enough even if the case is presented with Henry not having encountered any of the fakes, Goldman decided to tell the story that way. (Again, that’s just speculation.)
But if it really isn’t that intuitively solid that Henry doesn’t know in the unmodified story, we have good reason to modify the case. And the modified case has served my purposes well. (Because the fake barns have looked exactly like real barns, Henry still seems as justified in his judgment that he’s seeing a barn as he would have been if there had been no fakes, so, even with the modification, this example still seems, for instance, to be a case of justified, true belief that fails to be knowledge.)
Is it absolutely certain that Henry doesn’t know, even in the modified 1-for-20 (or 1-for-40) case? Of course not. But about the modified case, the judgment that Henry doesn’t know seems fairly solid to me, so far as premises of philosophical arguments go. But I wonder what others think