I’m grateful to Edward Feser for commenting on my work. We share a common starting point, namely our conviction that the qualities we encounter in experience cannot be fully accounted for in the purely quantitative terms of physical science, and hence that our conventional scientific worldview misses something out. But we disagree on how to rectify this error. I agree with Galileo (ironic, given the title of my book) that the qualities aren’t really out there in the world but exist only in consciousness. So I don’t think we need to account for the redness of the rose any more than we need to account for the Loch Ness monster (neither exist!); but we do need to account for the redness in my experience. Following Russell and Eddington I do this by incorporating the qualities of experience into the intrinsic nature of matter, ultimately leading me to a panpsychist theory of reality. Feser, in contrast, rejects Galileo’s initial move of taking the qualities out of the external world. The redness really is in the rose, the greenness really in the grass, etc., and hence we have a ‘hard problem’ not just about consciousness but also about the qualities in external objects.
A very similar critique was made of my work my Michelle Liu and Alex Moran in this special issue of the Journal of Consciousness Studies on my work, which is coming out later this year as a book called Is Consciousness Everywhere? I reply to Liu and Moran (and all the other contributors) here.
Feser’s view is standardly called ‘direct realism’ or ‘naïve realism’: the view that conscious perception (when it goes right) is essentially a relationship between the mind and the external world. According to direct realism, experiences are not inside the head but are rather ‘world-involving’: the red rose out there in the world is literally inside of (or at least partly constitutes) my visual experience of the red rose. The redness I directly encounter in my experience is not a property of my experience but of the rose itself.
I have a familiar philosophical concern with this view, which arises from thinking about hallucinations. If I’m hallucinating a red rose, then there’s no red rose out there in the world for me to be related to. So when it comes to hallucinations, at least, the experience must be in the head. The direct realist, then, is led to the view that veridical experiences (‘veridical’ is the technical term for experiences that present things as they really are) are radically different kinds of thing from hallucinations: the former are world-involving relationships, the latter are in the head. This view is known in philosophy of perception as ‘disjunctivism.’
For these reasons, Feser’s direct realism entails disjunctivism, and I think there’s a pretty good argument against disjunctivism. It was first formulated by my good friend Howard Robinson but further developed by Mike Martin. It goes as follows.
Consider a moment when Sara is veridically seeing a red rose at precisely 2pm. Now let’s imagine a genius evil scientist kidnaps Sara later that day, removes her brain and puts it in a vat, and then fiddles with it so that it’s in the exact same state it was at 2pm that day. Presumably, Sara’s brain in the vat will now be having an internal experience that makes it seem to her that it’s seeing a red rose (even though the brain doesn’t have any eyes, so isn’t seeing anything). But, given that at 2pm Sara’s brain was in the same state, then her brain at 2pm must have also generated an internal experience that made it seem to Sara that she’s seeing a red rose. Strictly speaking this doesn’t rule out direct realism: at 2pm Sara’s brain might have generated an internal experience (that made it seem to her that she’s seeing a red rose) and in addition Sara might have also had a world-involving experience (that also made it seem to have that she’s seeing a red rose). But the latter experience seems redundant, given that the former is sufficient to make it seem to Sara that she’s seeing a red rose. This argument persuades me that there aren’t really any world-involving experiences: experiences are all in the head (which is not to deny that experience inside our heads can put us in contact with reality outside of our heads).
(In fact, Mike Martin, who developed this argument, goes onto reject it, but I think the position he ultimately goes for is incompatible with the kind of anti-materialist view Feser and I agree on…I will write a paper about this at some point…).
Feser also suggests I don’t have good justification for panpsychism, but he doesn’t in fact consider my main argument for panpsychism, which is a simplicity-based argument. I have argued that panpsychism is the most parsimonious theory able to account for both the reality of consciousness and the data of third-person science. All things being equal, we should go for more parsimonious theories. So unless there’s some data we can point to that panpsychism is unable to account for, then panpsychism is the view we ought to go for.