My sense of the consciousness literature is that it’s a standard objection to dualism that it leads to epiphenomenalism (given reasonable assumptions about physics), and given epiphenomenalism, ‘we have no reason to believe that our reports of consciousness have any connection to the phenomenon of consciousness’, so dualism falsely implies that we don’t know that we are conscious and must be wrong. Though it’s a long time since I read this stuff. I think it’s discussed in ch.5 of The Conscious Mind under “The Paradox of Phenomenal Judgment”. I’ve just checked Chalmers’ later ‘The Character of Consciousness’ and sc.10 of ch.5 describes this as a standard objection to epiphenomenalist forms of dualism (and bear in mind the original version of that chapter goes back to the mid-90s), though he doesn’t actually cite any examples of people arguing this*. My sense is that ch.8 and 9 of Character of Consciousness are designed, among other things to address this sort of objection. My memory is that it’s discussed in Jackson’s original paper on the Knowledge Argument (the Mary the colour scientist in the black and white room thought experiment). Insofar as Eliezer thinks he has discovered something that “philosophers” have overlooked here, I think he’s just wrong. But by the same token, the general complaint “dualism entails epiphenomenalism, which is silly and self-undermining because it blocks knowledge of consciousness” is not some wild out to lunch belief of Eliezer’s; it’s well within the phil. mind mainstream! (Note that this is compatible with the original post here being right that Eliezer’s specific detailed reasoning on this topic is not good.)
What’s actually going on is that (not all) philosophers regard this as such a decisive objection to epiphenomenalist varieties of dualism or dualism in general, that the latter have definitely been refuted aren’t worth discussing (etc.) Though note that almost certainly some physicalists, maybe even many, do think this. But as long as there are still dualists who disagree, they will keep arguing about it in journals and treating dualists (relatively!) respectfully in published work: they have both selfish career incentives to do so (it makes for publications), but also, presumably they want to demonstrate the wrongness of dualism (ideally to dualists, certainly to bystanders.) There’s not much point in them taking the “this is like creationism or flat Earthism” high ground, when 1 out of 3 of their colleagues are dualists, whatever the physicalists own personal inside view credence in dualism. (Though to be clear, there are no doubt many physicalists who think dualism is wrong but not *obviously* wrong to.)
Actually, insofar as Eliezer has said “don’t listen to silly philosophers, they don’t even get the devastating objections to dualism that I outline here”, I actually think he has made the same mistake that you correctly diagnose Omnizoid as having made on FDT. As you say very often in philosophy all known views face objections that look, on their own devastating, but it’s also not clear that there is a further, different alternative that doesn’t face those objections**. In the clearest cases of this, logical paradoxes like the liar or the sorites, we can show to a fairly high standard of rigor that actually something that seems obvious and maybe even a “conceptual truth” must be false. So at least in those cases, the answer “dumb philosophers have missed an alternative that avoids all problems” is not very plausible. But in cases where things are murky and less rigorous there is always a temptation to take the objection that feels most convincing to you and go “how could anyone possibly endorse view X, given objection Y”, even if all the known alternatives to X face big problems too. This should be resisted, but not many people seem to be very good at resisting it, not even professional philosophers.
*Maybe people said it all the time in conversation but it didn’t really make it into print by the mid-90s, because pre-Chalmers few people defended dualism at length?
**In my personal view there often is such an alternative: namely “there is no determinate fact of the matter who is right on this issue, because the meaning of our terms isn’t precise enough to settle it”. But that’s not usually what philosophers as a group think about most of the disputes.
My sense of the consciousness literature is that it’s a standard objection to dualism that it leads to epiphenomenalism (given reasonable assumptions about physics), and given epiphenomenalism, ‘we have no reason to believe that our reports of consciousness have any connection to the phenomenon of consciousness’, so dualism falsely implies that we don’t know that we are conscious and must be wrong. Though it’s a long time since I read this stuff. I think it’s discussed in ch.5 of The Conscious Mind under “The Paradox of Phenomenal Judgment”. I’ve just checked Chalmers’ later ‘The Character of Consciousness’ and sc.10 of ch.5 describes this as a standard objection to epiphenomenalist forms of dualism (and bear in mind the original version of that chapter goes back to the mid-90s), though he doesn’t actually cite any examples of people arguing this*. My sense is that ch.8 and 9 of Character of Consciousness are designed, among other things to address this sort of objection. My memory is that it’s discussed in Jackson’s original paper on the Knowledge Argument (the Mary the colour scientist in the black and white room thought experiment). Insofar as Eliezer thinks he has discovered something that “philosophers” have overlooked here, I think he’s just wrong. But by the same token, the general complaint “dualism entails epiphenomenalism, which is silly and self-undermining because it blocks knowledge of consciousness” is not some wild out to lunch belief of Eliezer’s; it’s well within the phil. mind mainstream! (Note that this is compatible with the original post here being right that Eliezer’s specific detailed reasoning on this topic is not good.)
What’s actually going on is that (not all) philosophers regard this as such a decisive objection to epiphenomenalist varieties of dualism or dualism in general, that the latter have definitely been refuted aren’t worth discussing (etc.) Though note that almost certainly some physicalists, maybe even many, do think this. But as long as there are still dualists who disagree, they will keep arguing about it in journals and treating dualists (relatively!) respectfully in published work: they have both selfish career incentives to do so (it makes for publications), but also, presumably they want to demonstrate the wrongness of dualism (ideally to dualists, certainly to bystanders.) There’s not much point in them taking the “this is like creationism or flat Earthism” high ground, when 1 out of 3 of their colleagues are dualists, whatever the physicalists own personal inside view credence in dualism. (Though to be clear, there are no doubt many physicalists who think dualism is wrong but not *obviously* wrong to.)
Actually, insofar as Eliezer has said “don’t listen to silly philosophers, they don’t even get the devastating objections to dualism that I outline here”, I actually think he has made the same mistake that you correctly diagnose Omnizoid as having made on FDT. As you say very often in philosophy all known views face objections that look, on their own devastating, but it’s also not clear that there is a further, different alternative that doesn’t face those objections**. In the clearest cases of this, logical paradoxes like the liar or the sorites, we can show to a fairly high standard of rigor that actually something that seems obvious and maybe even a “conceptual truth” must be false. So at least in those cases, the answer “dumb philosophers have missed an alternative that avoids all problems” is not very plausible. But in cases where things are murky and less rigorous there is always a temptation to take the objection that feels most convincing to you and go “how could anyone possibly endorse view X, given objection Y”, even if all the known alternatives to X face big problems too. This should be resisted, but not many people seem to be very good at resisting it, not even professional philosophers.
*Maybe people said it all the time in conversation but it didn’t really make it into print by the mid-90s, because pre-Chalmers few people defended dualism at length?
**In my personal view there often is such an alternative: namely “there is no determinate fact of the matter who is right on this issue, because the meaning of our terms isn’t precise enough to settle it”. But that’s not usually what philosophers as a group think about most of the disputes.
I should have been clearer.
I wasn’t claiming Eliezer’s point was original, just especially clear and well-argued.
Then again, maybe if I looked into the literature I’d find others making this point in an even clearer and better argued fashion.
Cool, that makes sense.