Why are intuitions with narrower content so much more evidentially trustworthy or warrant-conferring than intuitions with broader content? Why is it that if many of our narrower intuitions conflict with some of our broader intuitions, we often tend to drop the latter and not the former?
Better to intuit that “water” doesn’t mean the same thing on Earth as on Twin Earth than to intuit semantic externalism. If we intuit the former, this is better evidence against semantic internalism than an intuition that semantic internalism is true would be evidence against it.
Better to intuit that n grains of sand is not a heap and that if n grains of sand is not a heap, then n + 1 grains of sand is not a heap than to intuit that there are no heaps. In this case, I think, our intuition that there are heaps trumps our intuitions of the premises. Perhaps the premises, combined, are “broader” or stronger than the intuition that there are heaps, since they are recursive, and so have an infinite number of instances. Perhaps that is because I already know that there are heaps on the basis, say, of my perceptual evidence and my intuitions that, in this or that case, what I am looking at is a heap.
Better to intuit that I don’t really know that that is the façade of a barn than to intuit that knowledge is not justified true belief. Sometimes I think that my intuition that knowledge is justified true belief trumps my intuition about fake barn country. Perhaps this is because I sometimes think that K = JTB has too many merits to give up so easily. Of course, most of the time, people take the intuition about fake barn country (along with intuitions about other Gettier cases) to trump K = JTB.
I think these examples show that, in general, narrower intuitions are better evidence for their claims than broader intuitions. They don’t show that a narrower intuition always trumps a conflicting broader intuition, since the broader intuition might have more going for it than the conflicting narrower intuition brings against it. They suggest that a narrower intuition trumps a conflicting broader intuition, ceteris paribus.
How do we explain all of this? Part of it is that a narrower claim just, in general, has more warrant or a higher probability, relative to some piece of evidence, than any broader claim (of which the narrower claim is “an instance”), relative to that same evidence. That is, if I see Mike park the car, that is better evidence that Mike knows how to park a car than it is evidence that everyone named “Mike” knows how to park a car, or that everyone Mike’s age knows how to park a car. So, my intuition that p is, in general, better evidence that p than it is evidence that (a stronger claim) p & q, and better evidence that p & q than it is evidence that (an even stronger claim) p & q & r, and so on. If my intuition is that all bachelors are unmarried men, that is better evidence that all bachelors are unmarried men than it is evidence that, say, all men are unmarried men, or that all bachelors are unmarried men and all male college students are unmarried men.
Part of it is that we get more disagreement with intuitions on broader claims. Since much of the time the conflicting intuitions of two individuals will carry just as much evidential weight, these sorts of disagreements don’t affect the evidential standing of the claims of interest one way or another. Intuitions about semantic internalism and semantic externalism won’t get us very far, because people’s intuitions differ and carry equal evidential weight.
But I think the biggest part of the explanation is this. The trustworthiness or warrant-conferring-ness of intuitions is often, if not always, grounded in linguistic competence. If one assents to a sentence in a certain context strictly because one knows how to use a language, then, I think, we generally treat that assent as (prima facie, defeasibly) warranted. The idea might be that if pure knowledge of a language alone prompts assent, then that sentence must command assent in that context purely in virtue of linguistic rules or conventions; and whatever rules or conventions philosophers have to obey, the linguistic rules or conventions of the language of inquiry are surely among them. Whether or not this meta-explanation is right, I think we do, in fact, generally treat such assent as warranted.
But how does one know that the assent is grounded in linguistic competence alone, and not some other feature of the assenter’s cognitive make-up? One test is whether other speakers of the assenter’s language behave similarly. This will yield some false positives, though, since speakers of the assenter’s language have more in common with her, cognitively, than the language alone. This could be what grounds the assent, not linguistic competence, and there is no very compelling reason to think that just any shared cognitive trait will issue warranted pronouncements or steer us towards the true and away from the false.
Another test has fewer false positives. Specify all of the relevant facts that do not formally or pragmatically entail the claim of interest. Then, query the subject on the claim. If she intuitively assents or fails to assent, what could explain it? If we’ve specified the facts the right way, and made sure she understands them, then her assent could not be based on failure to believe the right facts. Perhaps she has failed to reason with the facts the right way? That is one explanation of her assent. But if we have no antecedent reason to doubt her reasoning skills, this is implausible. Perhaps her tacit linguistic knowledge disposes her to respond one way, but some consciously held theoretical commitment trumps this more trustworthy disposition. We should try to rule out this possibility somehow, if we want our intuitions to help us decide the claims they are about. If we do successfully rule it out, I can only see one other alternative explanation. This is that the subject's assent (or failure to assent) is grounded in her linguistic competence.
How does this explain that intuitions with narrower content are more trustworthy than intuitions with broader content? First, because it is easier to specify all of the relevant facts for a narrow claim than for a broader claim. It is easier to say everything about fake barn country, a certain heap of sand, or Twin Earth than it is to say everything about justified true belief, heaps (or, for that matter, vagueness in general), and semantic externalism. That is one thing our second test requires we do. Another thing is to make sure that no conscious theory is over-riding what her linguistic competence disposes the subject to do. Narrower claims meet this requirement more easily, since they are less likely to be obviously consistent or inconsistent with a high-level theory than broader claims at the theoretical level. Lastly, the test requires that we make sure that our subject has not failed to reason with the premises correctly. Since it is easier to reason with fewer premises, ceteris paribus, and we need to specify fewer relevant facts for narrower claims, narrower claims are more likely to pass our second test than broader claims.