Jennifer Matey gave a very nice talk at William Paterson University last week, “Visual Constancies and the Representational Nature of Visual Experiences”. Much of talk concerned issues contested between direct and representational realists about perception (with some side-notes about disjunctivists). An interesting methodological/metaphilosophical issue came up in the ensuing discussion (interesting to me, perhaps, because I was the one who brought it up). It goes something like this.
From a certain point of view it’s quite hard to see exactly what’s contested between the direct and the representational realist and it’s likewise hard to tell how to adjudicate the dispute. To get in the right frame of mind, imagine trying to explain the debate to a Rortyean Antipodean: a person who speaks a language a lot like English, though it’s shot through with a lot more neuroscientific vocabulary than most English speakers know and is utterly devoid of words like “perception”, “experience”, “awareness”, “consciousness”, and “qualia”. Imagine further that the Antipodean has come across a direct realist (DR) and a representationalist (R) in the process of examining a brain in a vat (Vatty) and its non-envatted neural doppleganger (Normy). Both R and DR agree that Vatty and Normy are in the same neural state when Normy is facing a tree with open eyes in a well-lighted environment. Both R and DR agree that that Normy but not Vatty is having a veridical experience of a tree. But what is it that they are disagreeingabout? And more to the point of this post, what could they say to the Antipodean to convince him to pick a side on this issue?
The Antipodean can see quite clearly that there are relational properties involving trees that Normy’s brain but not Vatty’s instantiates. And the Antipodean can see quite clearly that there are non-relational neural properties that Normy’s and Vatty’s brains have in common. What the Antipodean doesn’t get, is what else there might be to say here. Are DR and R fighting over which parts of the universe to draw a line around and apply the label “physical substrate of visual awareness” to? If so, why bother?
When I get in the Antipodean’s frame of mind I’m tempted to assert the following general methodological principle: if you can’t explain what you’re talking about to an Antipodean, then maybe you’re not talking about anything.