None of this could be much comfort to a disconsolate Empiricist, since none of it is supposed to deny, even for a moment, that a lot of stuff that’s domain specific or species specific or both has to be innate in order that we shouldcome to have the concept DOORKNOB (or for that matter, the concept RED). But the issue isn’t whether acquiringDOORKNOB requires a lot of innate stuff; anybody with any sense can see that it does. The issue is whether itrequires a lot of innate intentional stuff, a lot of innate stuff that has content. All the arguments I know that say thatinnate intentional stuff has to mediate concept acquisition depend on assuming either that concept acquisition isinductive or that the explanation of the d/D effect is psychological or both. Well, where a primitive concept expressesa mind-dependent property, it is very unclear that either of these kinds of argument will work.
Maybe there aren’t any innate ideas after all.
Appendix 6A Similarity
‘Hey, aren’t you just saying that all that has to be innate in a DOORKNOB-acquisition device is the capacity to learn to respond selectively to things that are relevantly similar to doorknobs? And didn’t Quine say that years ago?’
No, I’m not and no, he didn’t. Not quite.
There are two ways to understand the claim that the process of acquiring DOORKNOB recruits an innate ‘similarity metric’. One is platitudinous, the other is committed to innate ideas—in effect, to the innateness of the conceptSIMILAR TO A DOORKNOB. The geography around here is pretty familiar, so we can settle for a quick tour.
On the first way of running it, the similarity story is just the remark that, given appropriate experience of doorknobs, creatures like us converge on a capacity to respond selectively to things that are like doorknobs in respect of theirdoorknobhood. This is perfectly self-evidently true; nobody reasonable could wish to deny it. It doesn’t, however, explainthe fact that we learn DOORKNOB from doorknobs; it just repeats the fact that we do. So construed, the similaritystory is completely neutral on the issues this chapter is concerned with, viz. whether the structures in virtue of whichwe are able to converge on selective sensitivity to doorknobhood need to be innate, and whether they need to beintentional.
On the other, unplatitudinous, way of running the similarity theory, it is itself a version of concept nativism: it’s the thesis that what’s innate is the concept SIMILAR TO A DOORKNOB. There seems, to put it mildly, to be no reasonto prefer that view to one that has DOORKNOB itself be innate. (Indeed, the first would seem to imply the second;since the concept SIMILAR TO A DOORKNOB is, on the face of it, a construct out of the concept DOORKNOB,it’s hard to imagine how anyone could think the one concept unless he could also think the other.) None of thisbothers Quine much, of course, because he pretty explicitly assumes the Empiricist principle that the innatedimensions of similarity, along which experience generalizes, are sensory. But Empiricism isn’t true, and it is time toput away childish things.
Quine’s story is that learning DOORKNOB is learning to respond selectivity to things that are similar to doorknobs. What the story amounts to depends, in short, on how beingsimilar to doorknobs is construed. Well, there’s a dilemma: ifbeing similar to doorknobs is elucidated by appeal to doorknobhood, then the story is patently empty; ‘How is the conceptthat expresses doorknobhood acquired?’ is the very question that it was supposed to be the answer to. If, on the otherhand, being similar to
doorknobs is spelled out by reference to properties other than doorknobhood, Quine has to say which properties these are, where the concepts of these properties come from, and how radical nativism with respect to them is to be avoided.
Like Quine, I’ve opted for the second horn of the dilemma. But, unlike Quine, I’m no Empiricist. Accordingly, I can appeal to the doorknob stereotype to say what ‘similarity to doorknobs’ comes to, and—since ‘the doorknobstereotype’ is independently defined—I can do so without invoking the concept DOORKNOB and thereby courtingplatitude.