Hohwy on Phenomenal Variability
In a new article at Mind & Language (free penultimate draft here), Jakob Hohwy argues that I'm wrong in my claim (e.g., here and here) that the enormous variation in people's reports about their stream of experience reflects a pattern of massive error in introspective judgment. Rather, Hohwy suggests, the enormous variability of introspective reports reflects a pattern of enormous variability in the target experiences being reported on -- variability that introspection captures accurately. (Hohwy does allow, however, that there may be massive error in some domains and under some introspective conditions.)
Consider, for example, these differences: Some people say that their visual imagery is as vivid and detailed as ordinary vision, while others say that they have extremely sketchy visual imagery or none at all. And yet self-reported high- and low-imagers seem to perform similarly on cognitive tests that apparently draw on visual imagery, like mental rotation tasks (see here and Ch. 3 of here). Some people say that they experience 30 or more degrees of stable visual clarity with indistinctness only outside that range, while others say that they visually experience only a tiny point of clarity (1-2 degrees) bouncing rapidly around an indistinct background (see here). Could such people all be right in their radically different claims? Hohwy admits that the burden of proof is on him.
Hohwy supports his view in a variety of ways, but I found his cases for the radical variability of imagery and emotion the most interesting. Imagery, he points out, serves a wide variety of cognitive purposes. Some purposes may require detailed imagery (e.g., remembering a scene in order to paint it) while others require only sketchy imagery (e.g., matching two figures in a mental rotation). (These are my examples, not Hohwy's.) The request simply to "form an image" of, say, the front of one's house, as in Francis Galton's questionnaire, and David Marks's, and in my own, is a request without a natural, contextually-given purpose. People may form radically different images when given an introspective questionnaire, images which they accurately report, despite being generally cognitively similar on imagery tasks with more constrained or natural goals. This is an excellent point (which Russ Hurlburt has also emphasized to me), and I agree that I haven't adequately addressed it in my writings on the introspection of imagery. When asked generically to "form an image of your house" some people might paint themselves a detailed two-dimensional scene, some might sequentially drift around thinking about a few visual details of emotional significance, and others might do a minimalist 3D sketch -- even if they all have the same underlying imagery capacities and experiences when in more cognitively constrained contexts.
Let me note two things, though, that I think tilt somewhat back in favor of attributing error rather than radical variability. First, when instructed to form an image in an introspective questionnaire in a context where their image-making capacities are naturally seen as the issue under test (as in Galton's and Marks's questionnaires, I think), most people will probably think that they've been asked to form as vivid and detailed a visual image as possible in a short time frame. The majority of respondents will thus, I'm inclined to think, tend understand the request broadly similarly. If so, it remains unexplained why people should radically differ in their responses unless those differences reflect either radically different imagery capacities (which seems not to be the case judging from behavioral tests) or some sort of inadequacy in respondents' introspective reports. Second, people also make radically different general claims and capacity claims about their imagery (e.g., Berkeley's claim that there is never indeterminacy in the contents of his imagery, contra Locke). Prima facie (though I don't know that this has been well tested) such differences seem unlikely to be mirrored by equally radically different cognitive capacities. Such differences are, I believe, somewhat more straightforwardly explained as due to introspective error (possibly arising from folk theory or psychological theory, overanalogy to outward visual media, or investment in a certain self-conception) than as due to variability in the demands of different cognitive tasks.
[Well, it looks like I won't be able to do justice to Hohwy's even more interesting claims about emotional variability without going overlong. So let me save that for a follow-up post soon.]