I said I was gonna stay off tumblr, but I felt like writing a post about zombies and I figure it can’t hurt if I don’t look at the dash otherwise.
None of the following is new, I’m sure, but I just want to mention it because I think it might be a better framework than talking about “epiphenoma” and the like
What I want to say is something like: maybe it’s just inherently misguided to imagine a world where people talk the way we do about consciousness, but in which there is actually “no one home,” because “there being someone home” is simply what it is like to be a physical system which talks about consciousness in the way we do.
The purely physical picture has a nice coherence to it. It sure looks like all of the stuff we say and do could, in principle, be explained as the result of the way our brains and bodies are set up. One example: when we talk about the “ineffability” or “indescribability” of consciousness, we tend to hone in on certain experiences in particular, usually “primitive” sensory experiences that can’t be decomposed into smaller parts. “Seeing a color” is the classic example – Mary the Color Scientist and so forth. I have this feeling that there is a very definite character to each of the colors I see – I recognize them instantly, as though they were friends. I have this recognition experience like “oh! there’s red!” where “red” is this definite, clearly defined thing. Then I see green and think “oh! there’s green! you’re very different from red, and I know exactly how!”
But these “definite personalities” and “differences” can’t be described. If I wanted to say how I tell one friend from another, I might describe differences in their facial shapes. If I want to say how I can tell Bob from John, I might describe a difference in their facial shapes. If I want to say how I tell red from green, I’m at a loss for words. (I can refer to things that are red, like saying “red is the color of spilled blood,” but that’s cheating – it’s like saying “I can recognize Bob because looks like the guy who did [a thing Bob has done].”)
If you are thinking in purely physicalist terms, it’s easy to guess why this might be true. We’re used to being able to describe our perceptions by breaking them down somehow. I look at my floor, see that it has a pattern of squares on it, and say “pattern of squares” – a concept that can be spelled out mathematically. But at a certain point, we get down to a level where the input we’re getting has no structure – it isn’t a pattern of units, it’s just a unit. We can’t recognize any internal structure inside “red.” It’s just the “you’re seeing red” fibers lighting up, or whatever. So it makes sense that this particular sort of experience would seem weird when we really think about it; that we’d point to it as an instance of how conscious perception is different from all other sorts of knowledge; that we’d talk about how Mary may know everything about red scientifically but will learn something new when her red fibers light up (or whatever).
The problem with this cheerful physicalist picture is, of course, that it seems to allow a world where our qualia “aren’t really there” – it explains why we talk about them without actually including them. This is about as absurd as you can get, because I’m as sure of my conscious experience as I am of anything.
But, as youzicha said a little while ago, sometimes the best way to fool someone into believing something is to make it true. In this case: maybe “phenomenal experience” arises precisely in those cases when a system is set up to talk about this weird, ineffable thing called “phenomenal experience,” in precisely the way we do talk about it. A rule of thumb might be: if you can build a mind that talks in this way, and does it as an emergent consequence of its overall structure rather than as some ad hoc additional “script,” then it’s probably conscious.
This might not be as absurd as it sounds. Compare to the case of free will. People seem more willing to bite the physicalist bullet on free will than on consciousness, probably because there can’t be “epiphenomenal” version of free will (if your “free will” has no effects, it isn’t really free will). People say: maybe everything really is deterministic, but we still experience “free” deliberation over actions and so forth, and all of that is real, and there’s no reason we should change the way we do that just because of some bottom-level fact about physics. This seems similar to what is described above: there’s a self-consistent physical picture where a system sees itself as “having free will” because of how it’s built, but the underlying determinism doesn’t mean it “doesn’t really have free will” – it’s just that a system that deliberates (and so forth) in a sophisticated enough way to “think it has free will” is precisely what we really mean by “something that has free will.” We could say: it’s impossible to be deluded about having free will, because if have the kind of mind that lends itself to belief in free will the way ours does, you’re as free as anything can be. Similarly, we could say: it’s impossible to be deluded about whether you are conscious, because if a physical system is inclined toward our kind of consciousness talk – “whoa, I perceive red in this, like, ineffable way, and I could imagine a being that acts the same way but doesn’t” – that means it’s conscious.
In other words: consciousness is what “being a physical system that can imagine a zombie version of itself” feels like from the inside.
