The eliminativist responds: The world would look the same to me (a complex brain process) if dualism were true. But it would not look the same to the immaterial ghost possessing me, and we could write a computer program that simulates an epiphenomenal universe, i.e., one where every brain causally produces a ghost that has no effects of its own. So dualism is meaningful and false, not meaningless.
The dualist responds in turn: I agree that those two scenarios make sense. However, I disagree about which of those possible worlds the evidence suggests is our world. And I disagree about what sort of agent we are — experience reveals us to be phenomenal consciousnesses learning about whether there’s also a physical world, not brains investigating whether there’s also an invisible epiphenomenal spirit-world. The mental has epistemic priority over the physical.
We do have good reason to think we are epiphenomenal ghosts: Our moment-to-moment experience of things like that (ostending a patch of redness in my visual field) indicates that there is something within experience that is not strictly entailed by the physical facts. This category of experiential ‘thats’ I assign the label ‘phenomenal consciousness’ as a useful shorthand, but the evidence for this category is a perception-like introspective acquaintance, not an inference from other items of knowledge.
You and I agree, eliminativist, that we can ostend something about our moment-to-moment introspective data. For instance, we can gesture at optical illusions. I simply insist that one of those somethings is epistemically impossible given physicalism; we couldn’t have such qualitatively specific experiences as mere arrangements of atoms, though I certainly agree we could have unconscious mental states that causally suffice for my judgments to that effect.
Eliminativist: Aren’t you giving up the game the moment you concede that your judgments are just as well predicted by my interpretation of the data as by yours? If your judgments are equally probable given eliminativism as given dualism, then eliminativism wins purely on grounds of parsimony.
Dualist: But the datum, the explanandum, isn’t my judgment. I don’t go ‘Oh, I seem to be judging that I’m experiencing redness; I’ll conclude that I am in fact experiencing redness’. Rather, I go ‘Oh, I seem to be experiencing redness; I’ll conclude that I am in fact experiencing redness’. This initial seeming is a perception-like access to a subjective field of vision, not something propositional or otherwise linguistically structured. And this seeming really does include phenomenal redness, over and above any disposition to linguistically judge (or behave at all!) in any specific way.
Eliminativist: But even those judgments are predicted by my theory as well. How can you trust in judgments of yours that are causally uncorrelated with the truth? If you know that in most possible worlds where you arrive at your current state of overall belief, you’re wrong about X, then you should conclude that you are in fact wrong about X. (And there are more possible worlds where your brain exists than where your brain and epiphenomenal ghost exist.)
Dualist: Our disagreement is that I don’t see my epistemic status as purely causal. On your view, knowledge and the object known are metaphysically distinct, with the object known causing our state of knowledge. You conclude that epistemic states are only reliable when they are correlated with the right extrinsic state of the world.
I agree with you that knowledge and the object known are generally distinct, but we should expect an exception to that rule when knowledge turns upon itself, i.e., when the thing we’re aware of is the very fact of awareness. In that case, my knowledge is not causally, spatially, or temporally separated from its object — at this very moment, without any need to appeal to a past or present at all, I can know that I am having this particular experience of a text box. I can be wrong in my inferences, wrong in my speculations about the world outside my experience; and I can be wrong in my subvocalized judgments about my experience; but my experience can’t be wrong about itself. You can design a map in such a way that it differs from (i.e., misrepresents) a territory, but you can’t design a map in such a way that it differs from itself; the relation of a map to itself is one of identity, not of representation or causality, and it is the nature of my map, as revealed by itself (and to itself!), that we’re discussing here.
Eliminativist: I just don’t think that model of introspection is tenable, given the history of science. Maybe your introspection gives you some evidence that physicalism is false, but the frequency with which we’ve turned out to be wrong about other aspects of our experience has to do a great deal to undermine your confidence in your map of the nature of your epistemic access to maps. I’m not having an argument with your visual field; I’m having an argument with a linguistic reasoner that has formed certain judgments about that visual field, and it’s always possible that the reasoner is wrong about its own internal states, no matter how obvious, manifest, self-evident, etc. those states appear.
Dualist: A fair point. And I can appreciate the force of your argument in the abstract, when I think about an arbitrary reasoner from the third person. Yet when I attend once more to my own stream of consciousness, I become just as confused all over again. Your philosophical position’s appeal is insufficient to overcome the perceptual obviousness of my own consciousness — and that obviousness includes the perceptual obviousness of irreducibility. I can’t make myself pretend to not believe in something that seems to me so self-evident.
Eliminativist: Then you aren’t trying hard enough. For I share your intuitions when I reflect on my immediate experiences, yet I’ve successfully deferred to science and philosophy in a way that blocks these semblances before they can mutate into beliefs. It can be done.
Dualist: It can be done. But should it? From my perspective, you’ve talked yourself into a lunatic position by reasoning only in impersonal, third-person terms. You’ve forgotten that the empirical evidence includes not only the history of science, but also your own conscious states. To me it appears that you’ve fallen into the error of the behaviorists, denying a mental state (phenomenal consciousness) just because it doesn’t fit neatly into a specific invented set of epistemological social standards. No matter how much I’d love to join you in asserting a theory as elegant and simple as physicalism, I can’t bring myself to do so when it comes at the cost of denying the manifest.
… and the discussion continues from there. I don’t think either position is meaningless. Claims like ‘nothing exists’ aren’t meaningless just because agents like us couldn’t confirm them if they were true; they’re meaningful and false. And it’s certainly conceivable that if the above discussion continued long enough, a consensus could be reached, simply by continuing to debate the extent to which science undermines phenomenology.
This is an excellent and fair summary of the debate. I think the one aspect it leaves out is that eliminativists differ from dualists in that they have internalized Quine’s lessons about how we can always revise our conceptual schemes. I elaborated on this long ago in this post at my old blog.
our concepts change and evolve with the growth of scientific knowledge; what is concievable now may become unconcievable later and vice-versa. Concepts are just tools for describing the world, and we can change them and reform them if we need to. This picture of science, familiar since Quine, is pressupposed by Dennett, but implicitly rejected by Chalmers.
I’m pretty confident Chalmers would disagree with this characterization. Chalmers accepts that our concepts can change, and he accepts that if zombies fall short of ideal conceivability — conceivability for a mind that perfectly understands the phenomena in question — then dualism will be refuted. That’s why the Mary’s Room thought experiment is about an ideally extrapolated reasoner. The weakness of such a thought experiment is, of course, that we may fail to accurately simulate an ideally extrapolated reasoner; but the strength is that this idealization has metaphysical significance in a way that mere failure of contemporary imagination doesn’t.
It may provide a fundamental theory or a list of them but not a list of fundamental entities the world is made of with a list of contingent laws of nature holding between them. What an entity such like the electromagnetic field is, is defined by what laws of nature it obeys and therefore by its relations with other entities.
If contemporary science’s best theory posits fundamental entities, then contemporary science posits fundamental entities. Science is not across-the-board ontologically agnostic or deflationary.
Unless I’m misunderstanding you, your claim that a physical theory is equivalent to its Ramsey sentence is a rather different topic. I think Chalmers would respond that although this may be true for physical theories at the moment, it’s a contingent, empirical truth — we happen to have discovered that we don’t need to perform any ostensive acts, for instance, in fixing the meanings of our physical terms. If science discovered an exception to this generalization, science would not perish; it would just slightly complicate the set of linguistic rituals it currently uses to clarify what it’s taking about.
But this shows that all the zombie arguments are question-begging, because to carry any force they must assume that there is something very special about consciousness that distinguishes it from other subjects for science in the first place.
This isn’t an assumption. It’s an inference from the empirical character of introspection. That is, it has a defeasible (quasi-)perceptual basis. Many eliminativists want it to be the case that dualists are question-begging when they treat introspective evidence as evidence, but introspective evidence is evidence. Chalmers does not take it as axiomatic, prior to examining the way his stream of consciousness actually looks, that there is a special class of phenomenal concepts.
I’m not a dualist, but I don’t think any of Chalmers’ arguments are question-begging. They just aren’t strong enough to refute physicalism; physicalism has too many good supporting arguments.
In the second paragraph you quote, I was not trying to make a strong statement about scientific theories being equivalent to Ramsey sentences, though I see how that is a natural interpretation of it. I meant to support my previous paragraph about the lack of a strong distinction between conceptual implications and definitions, and contingent/nomological laws. For each “fundamental law of physics”, there can be one axiomatization of physical theory where it is a contingent relation between fundamental entities, and another one where it is a definition or conceptual relation. It is central for Chalmers’ viewpoint that the relation between consciousness and functional states is irreducibly contingent, but this kind of law would be unlike any other one in physics.
This isn’t an assumption. It’s an inference from the empirical character of introspection. That is, it has a defeasible (quasi-)perceptual basis. Many eliminativists want it to be the case that dualists are question-begging when they treat introspective evidence as evidence, but introspective evidence is evidence. Chalmers does not take it as axiomatic, prior to examining the way his stream of consciousness actually looks, that there is a special class of phenomenal concepts.
I think you are mixing two things here: whether introspective evidence is evidence, which I agree to (e.g., when I “feel like I am seeing something green”, I very likely am in the state of “seeing something green”); and whether that “stuff” that when we introspect we describe with phenomenal concepts must necessarily be described with those concepts (instead of with more sophisticated and less intuitive concepts, for which the zombie/Mary’s Room/etc arguments would fail).
Yeah, Chalmers would agree that adding phenomenal consciousness would be a very profound break with the sort of theory physics currently endorses, and not just because it appears anthromorphizing.
whether that “stuff” that when we introspect we describe with phenomenal concepts must necessarily be described with those concepts (instead of with more sophisticated and less intuitive concepts, for which the zombie/Mary’s Room/etc arguments would fail).
I haven’t yet seen a concept that my phenomenal states appear to fall under, that blocks Mary’s Room or Zombie World. Not even a schematic, partly-fleshed-out concept. (And this is itself very surprising, given physicalism.)
The eliminativist responds: The world would look the same to me (a complex brain process) if dualism were true. But it would not look the same to the immaterial ghost possessing me, and we could write a computer program that simulates an epiphenomenal universe, i.e., one where every brain causally produces a ghost that has no effects of its own. So dualism is meaningful and false, not meaningless.
The dualist responds in turn: I agree that those two scenarios make sense. However, I disagree about which of those possible worlds the evidence suggests is our world. And I disagree about what sort of agent we are — experience reveals us to be phenomenal consciousnesses learning about whether there’s also a physical world, not brains investigating whether there’s also an invisible epiphenomenal spirit-world. The mental has epistemic priority over the physical.
We do have good reason to think we are epiphenomenal ghosts: Our moment-to-moment experience of things like that (ostending a patch of redness in my visual field) indicates that there is something within experience that is not strictly entailed by the physical facts. This category of experiential ‘thats’ I assign the label ‘phenomenal consciousness’ as a useful shorthand, but the evidence for this category is a perception-like introspective acquaintance, not an inference from other items of knowledge.
You and I agree, eliminativist, that we can ostend something about our moment-to-moment introspective data. For instance, we can gesture at optical illusions. I simply insist that one of those somethings is epistemically impossible given physicalism; we couldn’t have such qualitatively specific experiences as mere arrangements of atoms, though I certainly agree we could have unconscious mental states that causally suffice for my judgments to that effect.
Eliminativist: Aren’t you giving up the game the moment you concede that your judgments are just as well predicted by my interpretation of the data as by yours? If your judgments are equally probable given eliminativism as given dualism, then eliminativism wins purely on grounds of parsimony.
Dualist: But the datum, the explanandum, isn’t my judgment. I don’t go ‘Oh, I seem to be judging that I’m experiencing redness; I’ll conclude that I am in fact experiencing redness’. Rather, I go ‘Oh, I seem to be experiencing redness; I’ll conclude that I am in fact experiencing redness’. This initial seeming is a perception-like access to a subjective field of vision, not something propositional or otherwise linguistically structured. And this seeming really does include phenomenal redness, over and above any disposition to linguistically judge (or behave at all!) in any specific way.
Eliminativist: But even those judgments are predicted by my theory as well. How can you trust in judgments of yours that are causally uncorrelated with the truth? If you know that in most possible worlds where you arrive at your current state of overall belief, you’re wrong about X, then you should conclude that you are in fact wrong about X. (And there are more possible worlds where your brain exists than where your brain and epiphenomenal ghost exist.)
Dualist: Our disagreement is that I don’t see my epistemic status as purely causal. On your view, knowledge and the object known are metaphysically distinct, with the object known causing our state of knowledge. You conclude that epistemic states are only reliable when they are correlated with the right extrinsic state of the world.
I agree with you that knowledge and the object known are generally distinct, but we should expect an exception to that rule when knowledge turns upon itself, i.e., when the thing we’re aware of is the very fact of awareness. In that case, my knowledge is not causally, spatially, or temporally separated from its object — at this very moment, without any need to appeal to a past or present at all, I can know that I am having this particular experience of a text box. I can be wrong in my inferences, wrong in my speculations about the world outside my experience; and I can be wrong in my subvocalized judgments about my experience; but my experience can’t be wrong about itself. You can design a map in such a way that it differs from (i.e., misrepresents) a territory, but you can’t design a map in such a way that it differs from itself; the relation of a map to itself is one of identity, not of representation or causality, and it is the nature of my map, as revealed by itself (and to itself!), that we’re discussing here.
Eliminativist: I just don’t think that model of introspection is tenable, given the history of science. Maybe your introspection gives you some evidence that physicalism is false, but the frequency with which we’ve turned out to be wrong about other aspects of our experience has to do a great deal to undermine your confidence in your map of the nature of your epistemic access to maps. I’m not having an argument with your visual field; I’m having an argument with a linguistic reasoner that has formed certain judgments about that visual field, and it’s always possible that the reasoner is wrong about its own internal states, no matter how obvious, manifest, self-evident, etc. those states appear.
Dualist: A fair point. And I can appreciate the force of your argument in the abstract, when I think about an arbitrary reasoner from the third person. Yet when I attend once more to my own stream of consciousness, I become just as confused all over again. Your philosophical position’s appeal is insufficient to overcome the perceptual obviousness of my own consciousness — and that obviousness includes the perceptual obviousness of irreducibility. I can’t make myself pretend to not believe in something that seems to me so self-evident.
Eliminativist: Then you aren’t trying hard enough. For I share your intuitions when I reflect on my immediate experiences, yet I’ve successfully deferred to science and philosophy in a way that blocks these semblances before they can mutate into beliefs. It can be done.
Dualist: It can be done. But should it? From my perspective, you’ve talked yourself into a lunatic position by reasoning only in impersonal, third-person terms. You’ve forgotten that the empirical evidence includes not only the history of science, but also your own conscious states. To me it appears that you’ve fallen into the error of the behaviorists, denying a mental state (phenomenal consciousness) just because it doesn’t fit neatly into a specific invented set of epistemological social standards. No matter how much I’d love to join you in asserting a theory as elegant and simple as physicalism, I can’t bring myself to do so when it comes at the cost of denying the manifest.
… and the discussion continues from there. I don’t think either position is meaningless. Claims like ‘nothing exists’ aren’t meaningless just because agents like us couldn’t confirm them if they were true; they’re meaningful and false. And it’s certainly conceivable that if the above discussion continued long enough, a consensus could be reached, simply by continuing to debate the extent to which science undermines phenomenology.
This is an excellent and fair summary of the debate. I think the one aspect it leaves out is that eliminativists differ from dualists in that they have internalized Quine’s lessons about how we can always revise our conceptual schemes. I elaborated on this long ago in this post at my old blog.
I’m pretty confident Chalmers would disagree with this characterization. Chalmers accepts that our concepts can change, and he accepts that if zombies fall short of ideal conceivability — conceivability for a mind that perfectly understands the phenomena in question — then dualism will be refuted. That’s why the Mary’s Room thought experiment is about an ideally extrapolated reasoner. The weakness of such a thought experiment is, of course, that we may fail to accurately simulate an ideally extrapolated reasoner; but the strength is that this idealization has metaphysical significance in a way that mere failure of contemporary imagination doesn’t.
If contemporary science’s best theory posits fundamental entities, then contemporary science posits fundamental entities. Science is not across-the-board ontologically agnostic or deflationary.
Unless I’m misunderstanding you, your claim that a physical theory is equivalent to its Ramsey sentence is a rather different topic. I think Chalmers would respond that although this may be true for physical theories at the moment, it’s a contingent, empirical truth — we happen to have discovered that we don’t need to perform any ostensive acts, for instance, in fixing the meanings of our physical terms. If science discovered an exception to this generalization, science would not perish; it would just slightly complicate the set of linguistic rituals it currently uses to clarify what it’s taking about.
This isn’t an assumption. It’s an inference from the empirical character of introspection. That is, it has a defeasible (quasi-)perceptual basis. Many eliminativists want it to be the case that dualists are question-begging when they treat introspective evidence as evidence, but introspective evidence is evidence. Chalmers does not take it as axiomatic, prior to examining the way his stream of consciousness actually looks, that there is a special class of phenomenal concepts.
I’m not a dualist, but I don’t think any of Chalmers’ arguments are question-begging. They just aren’t strong enough to refute physicalism; physicalism has too many good supporting arguments.
Thanks for your comments!
In the second paragraph you quote, I was not trying to make a strong statement about scientific theories being equivalent to Ramsey sentences, though I see how that is a natural interpretation of it. I meant to support my previous paragraph about the lack of a strong distinction between conceptual implications and definitions, and contingent/nomological laws. For each “fundamental law of physics”, there can be one axiomatization of physical theory where it is a contingent relation between fundamental entities, and another one where it is a definition or conceptual relation. It is central for Chalmers’ viewpoint that the relation between consciousness and functional states is irreducibly contingent, but this kind of law would be unlike any other one in physics.
I think you are mixing two things here: whether introspective evidence is evidence, which I agree to (e.g., when I “feel like I am seeing something green”, I very likely am in the state of “seeing something green”); and whether that “stuff” that when we introspect we describe with phenomenal concepts must necessarily be described with those concepts (instead of with more sophisticated and less intuitive concepts, for which the zombie/Mary’s Room/etc arguments would fail).
Yeah, Chalmers would agree that adding phenomenal consciousness would be a very profound break with the sort of theory physics currently endorses, and not just because it appears anthromorphizing.
I haven’t yet seen a concept that my phenomenal states appear to fall under, that blocks Mary’s Room or Zombie World. Not even a schematic, partly-fleshed-out concept. (And this is itself very surprising, given physicalism.)