Moreover, once you assume that the brain operates in compliance with physical law, qualia must not play any role in the brain’s operation.
Not true if “qualia” refers to a high-level property of some matter.
Next consider a plant that has not been watered for several days, nearly dying. You water it, and soon its leaves stretch again and regain their vitality. Should you invoke the qualia of “thirst” or “slaking thirst” to explain what happened?
These explanations aren’t actually completely stupid; if the plant is optimizing then its optimization could possibly neatly be described by analogy with properties of human optimization that are perceivable in qualia. Maybe empathizing with a plant is a good way of understanding its optimization.
Of course, the analogy isn’t great (though is much better in the case of large animals), hence why I’m saying the explanations are “not completely stupid” rather than “good”.
Well, if a non-physical cause plays a role in any process, than some of physics’ most revered laws, such as energy and momentum conservation, are violated.
False dichotomy, the explanations may apply to different properties of the process, or to different levels of analysis of the process. (I am, here, rejecting the principle of unique causality)
Software, just like hardware, is a physical configuration of matter.
“Is” seems like overeager reductionism. Telling what program a given computer is running, based on its physical configuration, is nontrivial.
Identity/double-aspect theory: The quale and the percept are one and the same process, only perceived as different.
This seems true. Note that “perceived as different” is doing a lot of work here. Qualia are known “directly” in a way that is close to metaphysically basic, whereas percepts are known indirectly, e.g. by looking at a brain scan of one’s self or another person (note, this observation is also known through qualia, indirectly, since the brain scan must be observed). These are different epistemic modalities, that could nonetheless always yield the same information due to being two views on the same process.
This can be succinctly put as the Qualia Inaction Postulate: Any behavior would be exactly the same have there been no qualia.
False under identity/double-aspect theory. Because changing qualia means changing percepts too.
The fact that humans are baffled by the Percepts-Qualia Nonidentity, and express this bafflement by their observable behavior, is a case where qualia per se – as nonidentical with percepts – play a causal role in a physical process.
“Percept” as he uses the term refers to the entire brain processing starting from seeing something, including the part of the processing that processes things through world-perception ontology, self-concepts, etc. So “qualia per se—as nonidentical with percepts” is already assuming the falsity of identity/double-aspect theory.
Notice, first, that by this explanation-away the physicalist position commits itself, for the first time, to a falsifiable prediction: When future neurophysiology becomes advanced enough to point out the neural correlates of false beliefs, a specific correlate of this kind would be found to underlie the bafflement about qualia
Why would there be “neural correlates of false beliefs”? The brain can’t tell that all of its false beliefs are false; that would require omniscience.
If a proof is ever given that an intelligent system, by virtue of physical laws alone, must state that it has qualia which are nonidentical with percepts, then the age-old Mind-Body Problem would finally get a definite solution – a physicalist one. The Percept-Qualia Nonidentity would turn out to be nothing but an unfortunate misperception, inherent to all intelligent systems, and the problem would turn out to be a pseudo-problem.
I believe my post gives something close to such a proof (not complete, but suggestive).
Chalmers has struggled with a similar idea in his discussion of “zombies.” These creatures are very instructive. Imagine intelligent beings that resemble us in every detail of our physiology, neuroanatomy
and chemistry, but have no qualia. This, recall, is perfectly consistent with physics – in fact, as noted above, zombies accord with physics more than the existence of non-zombies.
Zombies may be ruled out philosophically/metaphysically/etc without being ruled out by physics. So assuming zombies are possible is already baking in assumptions.
Notice that in this case we can determine with certainty the cause of this bafflement. Since Charmless is man-made, we can rule out the possibility that his bafflement is the result of some pre-installed “bug”
such as an explicit command to express bafflement or some deliberate misperception imposed on it. In other words, we can rule out any cause to Charmless’ assertion about having qualia other than his really having them.
Being susceptible to optical illusions doesn’t have to be explicitly programmed in. This is assuming all misperceptions are deliberate which is false (it assumes a kind of omniscence).
Next ask Charmless: Can you conceive of a duplicate of you (henceforth Harmless) who is identical to you but lacks Q? His answer, by (3), must be “No; unmediated percepts must occur by physical law.”
I don’t see at all how this follows.
.......
In summary: the article seems like a confused mess, making both technical errors and questionable metaphysical assumptions, such that it neither rules out percept-qualia identity nor epiphenomenalism.
Responding to a few points from his article:
Not true if “qualia” refers to a high-level property of some matter.
These explanations aren’t actually completely stupid; if the plant is optimizing then its optimization could possibly neatly be described by analogy with properties of human optimization that are perceivable in qualia. Maybe empathizing with a plant is a good way of understanding its optimization. Of course, the analogy isn’t great (though is much better in the case of large animals), hence why I’m saying the explanations are “not completely stupid” rather than “good”.
False dichotomy, the explanations may apply to different properties of the process, or to different levels of analysis of the process. (I am, here, rejecting the principle of unique causality)
“Is” seems like overeager reductionism. Telling what program a given computer is running, based on its physical configuration, is nontrivial.
This seems true. Note that “perceived as different” is doing a lot of work here. Qualia are known “directly” in a way that is close to metaphysically basic, whereas percepts are known indirectly, e.g. by looking at a brain scan of one’s self or another person (note, this observation is also known through qualia, indirectly, since the brain scan must be observed). These are different epistemic modalities, that could nonetheless always yield the same information due to being two views on the same process.
False under identity/double-aspect theory. Because changing qualia means changing percepts too.
“Percept” as he uses the term refers to the entire brain processing starting from seeing something, including the part of the processing that processes things through world-perception ontology, self-concepts, etc. So “qualia per se—as nonidentical with percepts” is already assuming the falsity of identity/double-aspect theory.
Why would there be “neural correlates of false beliefs”? The brain can’t tell that all of its false beliefs are false; that would require omniscience.
I believe my post gives something close to such a proof (not complete, but suggestive).
Zombies may be ruled out philosophically/metaphysically/etc without being ruled out by physics. So assuming zombies are possible is already baking in assumptions.
Being susceptible to optical illusions doesn’t have to be explicitly programmed in. This is assuming all misperceptions are deliberate which is false (it assumes a kind of omniscence).
I don’t see at all how this follows.
.......
In summary: the article seems like a confused mess, making both technical errors and questionable metaphysical assumptions, such that it neither rules out percept-qualia identity nor epiphenomenalism.