Last time around, Thomas Nagel (1974) came to the rescue for the dualist: we after all can know that there are other minds. Notice, however, that the dissolution of skepticism about other minds rests on the notion of similarity between subjects. This similarity has to be physical/behavioral or else risk begging the question ‒ one cannot argue for access to phenomenological facts about others by assuming phenomenological similarity with them. So, in Nagel’s view, physical and behavioral similarities allow us to know what it is like to be someone else.
Enter again zombies. Zombies, by definition, are physically and behaviorally identical to persons. They even will claim, without lying, to have subjective experiences. Now assume that Alice is a person while Bob is a zombie. Then, according to Nagel, Alice would know what it is like to be Bob. This gives rise to serious tensions. Would it feel like something for Alice to know what it is like to be Bob? Or would it feel like nothing? If the former, then either Bob would not, contrary to my hypothesis, be a zombie, or Nagel’s argument for other minds fails. If the latter, then we would have a way of picking out zombies in our midst, which seem rather puzzling. We would, in stark opposition to all physical and behavioral evidence, just know that someone is a zombie. Further, this also undermines Nagel’s claim that physical/behavioral similarities are sufficient for justified beliefs about the phenomenological experiences of others.
It seems that one cannot at the same time accept the possibility of zombies and have justified beliefs concerning the phenomenological character of others’ experiences. At the same time it seems that one cannot adopt Nagel’s view on the intrinsic nature of consciousness without leaving the door open for the zombie argument. It seems that, in the end, one can only simply assert that despite our ignorance, others do, indeed, have experiences with phenomenological content.
I propose that the way out of this problem is to adopt a relational view on conscious properties. This will both defuse the zombie argument and allow for Nagel’s argument for the existence of other minds to stand. This would, however, undermine Nagel’s argument for the inaccessibility of the phenomenological properties of the experiences of, for instance, bats. Daniel Dennett, basing his approach on what he calls heterophenomenology, agrees:
When we arrive at heterophenomenological narratives that no critic can find any positive grounds for rejecting, we should accept them […] as accurate accounts of what it is like to be the creature in question. That, after all, is how we treat each other. […] I am not shifting the burden of proof [wrt. bats] but extending the normal, human, burden of proof to other entities.Dennett 1991, pp. 443–444, boldface emphasis mine.
Heterophenomenology is the study of a subject’s subjective experiences through taking seriously their reports of their experiences. The reports do not necessarily have to be verbal. (Dennett 2001). This is obviously behavioristic: we accept the behavior of the studied creatures as proof of their consciousness.
It might be objected that under a relational view one will on occasion treat entities that are not conscious as conscious beings. We might, as an example, get taken in by clever devices designed to fool us to think of them as conscious. But is this not better than the alternative? That is, better than denying the consciousness of our fellow beings in order to save our intuitions about the intrinsic properties of consciousness?
Dennett, D. C. (1991). Consciousness explained. London: Penguin Books.
Dennett, D. C. (2001). Are we explaining consciousness yet? Cognition 79: 221‒237.
Nagel, T. (1974). What is it Like to Be a Bat? Philosophical Review, 83: 435–450.