Month: October 2009

The Matrix & Nonphysical Properties

Richard Brown 3 Comments

(cross-posted at Brains)

I have long wondered what dualists mean when they speak of nonphysical properties. Today I was reading Chalmers’ paper The Matrix as Metaphysics and he says something that may shed some light on the way in which he thinks of nonphysical properties. He argues that the matrix scenario can be construed as a metaphysical hypothesis about the ultimate nature of the physical world. If this is right then there is a sense in which dualism is true. The mind is a distinct entity that exists outside of physical space-time and causal interacts with the physical body. This is because the physical theory that is true of reality in the matrix is a computational theory on which the ultimate things which exist are bits (zeros and ones). Thus brains in the matrix are ultimately composed of bits and when people in the matrix talk about brains they ultimately are talking about bits. The brain which is outside of the matrix is not composed of bits (let us assume). It is ultimately composed of something else (let’s say strings). Thus the brain outside the matrix, when viewed from the perspective of someone who is in the matrix, is nonphysical. It is not something that could be deduced from a completed matrix microphysics (which would be phrased in terms of ones and zeros).

One might wonder whether a completed matrix physics would have to be supplemented with (from the perspective of the matrix) nonphysical laws in order to capture outside the matrix facts or whether we might view the truly completed matrix physics as being expanded to include the outside the matrix physics. On this latter view the laws of matrix-physics would be a special subset of the laws of outside-physics. If this were true then the matrix-physics would not be complete until it was expanded to include outside-physics and physicalism could still be true. One might also wonder whether people in the matrix had largely true outside-physics beliefs since the matrix world is a deliberate simulation of outside-physics.

But even setting aside these issues there are strange results. Suppose that physicalism is true and that consciousness is a purely physical property of the brain. Let us also assume that this is true of a brain that is not in a matrix scenario. Call this scenario 1. Now imagine that a physical duplicate of this physicalist brain that has been in a matrix scenario since birth Call this scenario 2). Then physicalism is true in scenario 1 and dualism is true of scenario 2. But these brains are physically identical! Furthermore this shows that we could not resolve the dispute between the physicalist and the dualist until one was in a position to determine whether or not one is in a matrix scenario. Since Chalmers himself admits that he cannot a priori rule out that he is not in a matrix scenario he must also admit that he is not in a position to a priori tell if physicalism or dualism true. So, suppose that we are actually in a matrix scenario then conceiving of zombies is just conceiving of a computer simulation composed completely of NPCs (non-player characters). But this doesn’t show that physicalism is false, since physicalism is best construed as the claim that lines up with the first brain; since with this understanding of nonphysical physicalism turns out to be nothing but the hypothesis that we are not in the matrix.

But even if we were in the matrix there is a sense in which we can say that physicalism is still ultimately true since in the above envisioned world qualitative properties turn out to be identical to properties which are physical in terms of outside-physics (since these properties are the very same as the ones in the world where physicalism is true).

Zoombies are creatures that are nonphysically identical to me in every respect and which lack nonphysical qualitative properties. I have in the past suggested that one way to conceive of zoombies is as Cartesian minds that only have thoughts but no qualia but now we can put it in terms of matrix scenarios. A zoombie has all of the same nonphysical properties that I in fact do. Suppose that I am in fact in scenario 2 above. Then a creature that has all of the nonphysical properties that I in fact do will have a brain that is identical to my outside-brain. This is to imagine scenario 1.

The traditional zombie is a creature that is physically identical to me and lacks consciousness. Now suppose that I have a zombie twin who is in a matrix scenario since birth. My matrix zombie twin has nonphysical properties (which are the very same properties that I physically have) but no qualitative properties. So, whether one has nonphysical properties or not is simply a matter of whether one is in the matrix or not. Chalmers’ defense of nonphysicalism can thus be seen as a defense of the claim that we are in the matrix.

Busy Bees Busily Buzzing ‘Bout

Richard Brown 1 Comment

This last week was a very busy one. As you may have noticed from the side bar the call for papers for Consciousness Online is now out…spread the word!

Tuesday I attended a talk/discussion of a paper by Ned Block on Attention and direct realism. Direct realism, roughly, is the view that when one has a veridical experience, say of the subway train coming into the station, the phenomenology of one’s experience is is determined by, or is constituted by, the properties that the object actually has. So on this view when one sees the subway one is somehow directly in contact with the physical object. This is contrasted with the view that one’s phenomenology is instead determined by, or constituted by some kind of mental representation that is perhaps caused by a physical object but which represents the physical object with a set of mental properties.

Block was arguing that direct realists can’t explain a certain fact about attention. His argument revolved around an interesting phenomenon discovered in attention research. If one is staring at a fixed spot and while doing that focuses one’s attention on one of three circles that are interlocked (something that is hard but can be done) one sees the circle one is attending to as brighter than the others. With practice one is able to move ones attention around the three circles and light them up as one goes. Given this some researchers took two gratings one of which was slightly dimmer than the other and what they found was that when the subjects attended to the fixation spot they could tell which of the two gratings was actually brighter than the other. But when they attended to the fixation point and shifted their attention to the dimmer patch they judged it to be the same brightness as the other patch; that is the two patches looked equally luminous. Block’s argument was then that the direct realist did not have any objective thing in the figure that they could point to to explain the difference in phenomenology. the figures stayed the same. Nor did they have any principled reason to say that one of the two perceptions was illusion and the other veridical.

On Friday I went to Jeremy Grey’s talk at the cuny cog sci speaker series. he was presenting data on the relationship between intelligence, as measured by standard psychological measures correlates with self-control. He was arguing for what he called the Individual Differences view. He started with a famous and intriguing study that found a correlation between self-control in 6 years olds and their subsequent performance on the SAT’s. Kid were given the following two options. They could either take a marshmallow that sitting on the table in front on them right now or they could wait until the experimenter returned and have two marshmallows. The experimenter then left and the children were videoed. Some of the kids were able to wait for the two marshmallow reward while others gave in immediately and ate the one that they had in front of them. What was surprising was that 12 years later when they took their SATs the ones who did best were those that waited longest for the two marshmallow reward. That is, the longer they were able to resist the marshmallow in front of them and wait for the return of the experimenter (some made it others didn’t) the higher their SAT scores were. Grey did a series of studies on adults to test the relationship between intelligence and self control and he found that there was indeed this relationship. There were, however, some people who scored high on the standardized tests but also scored high on impulsivity tests (that is they would be classified as high intelligence and low self control). The even more surprising thing was that if you factored in a certain kind of genetic variation which results in a variation in the dopamine receptors one saw that the outliers had this variation while those who conformed to the model did not. He also pointed to a study which suggested that pre-school children who participated in daily self-control exercises improved their performance on standardized IQ tests and so there is room for optimism that one is not stuck at one’s current IQ/self-control level.