In closing, let me mention an important background issue concerning which Engel and I appear to have different views. Engel, I take it, holds that the disagreement in intuitive judgments regarding concept application should be regarded as epistemically troublesome in much the way that disagreement about introspective judgment is regarded as epistemically troublesome. The idea is that in both cases there are objective facts of the matter, and the existence of widespread disagreement indicates that significant numbers of individuals are systematically mistaken about what those facts are.
Although I am inclined to accept this diagnosis when it comes to many introspective disagreements, I do not find it particularly plausible when it comes to disagreements concerning intuitions of concept application. Here’s why. Suppose that Weinberg and his collaborators are right when they suggest that low-socioeconomic status individuals are disposed to apply the concept <knowledge> in contexts where high-socioeconomic status (SES) individuals are disposed to withhold it (Weinberg et al. 2001). Would it follow (as Engel seems to assume) that at least one of these groups is mistaken about a matter of objective fact? I don’t think so. It seems to me more plausible to assume that low-SES subjects and high-SES subjects simply have different concepts (or “conceptions”, if you prefer) of knowledge, and each of them is applying its own concept correctly. The two concepts are similar enough to be both associated with the single word “knowledge”, but there is no case for regarding one of these concepts as superior to the other, or for thinking that only one of them truly captures the essence of knowledge. They are simply different concepts.
If this is right, then apparent disagreement between the judgments of low-SES subjects and high-SES subjects about whether or not S knows that P is not substantive in the way in which most introspective disagreement appears to be. Moreover, it seems to me that something similar should be said concerning many (if not all) disputes about the application of other central philosophical concepts. (One needs to take the possibility of performance errors into account here, but such problems will typically be minimized in philosophical contexts.) But I wouldn’t want to commit myself to this account of all intuitive disputes. In particular, it seems to me that introspective disputes concerning modal matters are likely to to be substantive in a way in which disagreements about intuitions regarding concept application are not.