This is a tangential thought from way back, that I’d been procrastinating on converting from scrawl to proper prose. (It’s still untidy, but I’ve figured that if I’m going to post it only when it’s been tidied, then it’ll never be posted.) It concerns an argument in Brian Weatherson’s ‘Are Humeans Out of Their Minds?‘. Weatherson is mainly responding to an argument by John Hawthorne about whether causation is extrinsic. My concern, though, is not with his main response, but with his argument against one of Hawthorne’s claims, a secondary issue in the paper.
Hawthorne’s claim is:
An intrinsic duplicate of any region wholly containing me will contain a being with my conscious life.
Seems plausible enough. But Weatherson argues that the following example of what he calls totality qualia undermines the intuitive case for Hawthorne’s claim:
Tweedledee is facing a perfectly symmetrical scene. His visual field is symmetric, with two gentle mountains rising to his left and his right and a symmetric plain in between them. All he can hear are two birds singing in perfect harmony, one behind his left ear and one behind his right ear. The smells of the field seem to envelope him rather than coming from any particular direction. There is a cool breeze blowing directly on his face. It’s a rather pleasant scene, and the overwhelming feeling is one of symmetry.
Tweedledum is very much like Tweedledee. Indeed, Tweedledum contains a duplicate of Tweedledee as a proper part. But Tweedledum also has some sensors in his skin, and brain cells in what corresponds to a suspiciously empty part of Tweedledee’s brain, that allow him to detect, and feel, where the magnetic fields are in the vicinity. And sadly, though Tweedledum is facing a duplicate of the scene facing Tweedledee, there is a major disturbance in the magnetic field just to Tweedledum’s left. This produces a jarring sensation in Tweedledum’s left side. As a consequence, Tweedledum does not share Tweedledee’s feeling of symmetry.
Whether a picture is symmetric is a property of its internal features, but it is also a feature that can be destroyed without changing the internal features by just adding more material to one side. It is a totality property of pictures, a property the picture has because it stops just where it does. Similarly, totality qualia are qualia that we have in part because we don’t have any more feelings than we actually do. Feelings of symmetry are totality qualia in this sense, as are many of the feelings of calm and peacefulness associated with Tweedledee’s state. It is not intuitive that totality qualia should be intrinsic to a region. Indeed, it seems intuitive that a duplicate of me that was extended to produce more sensory features would lack these feelings. Hence a duplicate of me would not share my conscious life in all respects, so Hawthorne’s [claim] is also false.
Note that that final sentence quoted contains an invalid inference. Hawthorne’s claim is that a region that is a duplicate of a region containing you would contain at least one being that has your conscious life. It’s quite possible that it also contains beings that do not share your conscious life. So the mere fact that a duplicate of you would not share your conscious life under some conditions does not undermine Hawthorne’s claim.
In other words, we shouldn’t be talking about the conscious lives of duplicates of you, specifically. We should be talking about duplicates of regions containing you, and the conscious lives that these duplicated regions contain. In the final paragraph quoted, Weatherson seems to be arguing against the claim that any duplicate of me will itself share my conscious life in all respects. But this is different from the claim that any duplicate of a region containing me will contain a being that shares my conscious life.
Once we see that Hawthorne’s claim deals with duplicating regions and not just the being itself, we can see that totality qualia don’t have the implications Weatherson thinks they do. Because if we are duplicating a region that contains the being minus the region containing the sensors that cause totality qualia, then the duplicate itself is also going to be a region containing the being but not the relevant sensors, and hence the being in that region would have the same totality qualia as its duplicate. If, on the other hand, we are duplicating a region that contains the being and the region containing the symmetry-upsetting sensors, then the duplicate will also contain the being and the sensors. Once again the conscious life of the being is duplicated.
Put another way, in order to check Hawthorne’s claim, it doesn’t do, as Weatherson does, to have one region containing the being but without the sensors, and then duplicate just the being-without-sensors, and put this duplicate into a region containing sensors. The larger region-with-sensors isn’t a duplicate of the first region, so it’s not relevant to Hawthorne’s claim. On the other hand, if we try to dodge this by taking the region to be duplicated to be just the being-without-sensors, then when we duplicate said region, all we’d get is a region containing a being-without-sensors. Which corroborates Hawthorne’s claim.
Suppose we take the latter course — our duplicated region is just the region that consists of the being-without-sensors, and nothing else (I think this is the duplication that Weatherson wants us to imagine, in his argument). Weatherson could then say that that region containing a being-without-sensors could be embedded in a world that has, in fact, sensors at the requisite locations. That world would then contain a being whose sensation of symmetry is upset.
That’s for the world in which the region-without-sensors is embedded. But for the purposes of evaluating Hawthorne’s claim, we want to know if the region-without-sensors contains a being with an upset sense of symmetry, since that’s the region being duplicated; not any larger region. If the region-without-sensors in this new world-with-sensors is indeed a duplicate of the original region-without-sensors, then it would seem that any effects on the being’s brain (and hence his conscious life — I’m assuming physicalism here, obviously) that are due to the sensors must be confined to regions in the world outside of the region-without-sensors. So while it would be accurate to say that that world contains a being with a sense of asymmetry, it’s not at all clear that we would say that the region-without-sensors contains a being with a sense of asymmetry. Does a region containing me, minus the region of space occupied by my left kidney, contain a person two kidneys, or a person with one kidney? If you pick the latter answer, then I don’t see why one should say that the region-without-sensors contains a being with an upset sense of symmetry. After all, all the “upset” is outside that region. And what if I ask if the region taken up by my right kidney contains a person with two kidneys? Does any region, even a point, that is a proper part of the region taken up by my entire body contain a person with two kidneys?
One might try to get around this by arguing that you can’t have two conscious beings in the same world such that one is a part of the other. Then you could say that there is only one conscious life that we can assign to any given region and its proper parts, and somehow argue towards discounting the conscious life that is unaffected by the sensors in favour of the conscious life that is affected by the sensors. However, even if we accept the principle of having only one conscious life assigned to a being and its proper parts, I see no reason to always decide in favour of the conscious life that incorporates “more sensors”.