Monday, August 6, 2012

Consciousness, Information, and the Interpretation Problem

One of the greatest mysteries of modern science involves understanding the nature of consciousness. There are currently many competing theories for the origins of consciousness. Although a clear solution is not yet in sight, nevertheless, there are many things that I believe that we can say about the problem now.

Two competing popular theories of consciousness are Material Property Dualism (MPD), and Functional Property Dualism (FPD). Both FPD and MPD are a variety of Property Dualism, that claims that something "more" than the structure and dynamics of physics is needed to explain consciousness. MPD claims that consciousness is inescapably tied to the matter that makes up our brains, while FPD claims that it is only the functional properties of our minds that is important, and that a simulation of a brain on a computer would thus have the same subjective experiences as does the biological brain. Personally, I prefer neither of these camps, but instead subscribe to a form of Representational Functionalism (RF), that claims that nothing more than the structure and dynamics of physics is needed for consciousness. Nevertheless, I think that there is value in comparing the arguments for MPD with those for FPD, since I believe that there are compelling reasons to prefer FPD over MPD if one is forced to chose between these two theories.

A major criticism of the computational model of consciousness raised by Material Property Dualists, against both FPD and RF, is that all information must be "interpreted" before it could mean anything, or have qualia or consciousness, while Functional Property Dualists claim that it is the functional properties of the system that carries the dual properties that lead to consciousness. MPD posits that only matter can carry the "property" of consciousness, a "dual" property, beyond its causal properties, which form the structure and dynamics of physics. It is easy to understand why they feel this way. After all, why would nothing more than a bunch of ones and zeros have any subjective experience, no matter how much complexity is contained in the organization of the ones and zeros. This is all very intuitively pleasing. And a similar argument seems to show that the structure and dynamics of physics alone shouldn't lead to experience either. It should lead to all the behavior we have, including our claims to experience, but (these people argue) one can imagine all that structure and dynamics taking place like the wheels of a clock, completely absent any subjective experience. RF, which I prefer, responds to this criticism by claiming that nothing "more" than the structure and dynamics of physics is actually needed, even though it intuitively feels like something more is needed (our intuitions are wrong). In contrast, FPD gets around this argument by admitting that something "more" is indeed needed, but they tie the "more" to the information/functional properties of the system instead of to the matter. Supporters of MPD usually respond to this argument by claiming that the information in the functional system needs something to help "interpret" it correctly, and that the ones and zeros by themselves are simply random bits of information, with no proper interpretation, and thus, with no experience. Thus, they claim that the "more" must reside in the fundamental properties of matter in some way.

On the surface, these arguments seem to be quite compelling. However, the Maxwell's Demon thought experiment, indicates something strange. We know from relativity that we can turn matter into energy and  vice versa. But now we also know that we can also convert INFORMATION into matter or energy and vice versaThis has important implications for the whole consciousness debate between MPD and FPD. 

Why? Because it seems to mean that the universe is made of something fundamental, namely matter / energy / information, and that these three things are nothing more than three different manifestations of the same fundamental entity. Much as water, steam, and ice are all different manifestations of the same fundamental entity. Thus, if matter can carry some "fundamental" interpretation that allows consciousness (as MPD claims), then so can information (as FPD claims). And there is no reason to suppose that matter is any "better" at carrying this fundamental property that allows for the interpretation of experience than is information. Therefore, inasmuch as the single objection to FPD (proper interpretation) has been removed, and there are compelling reasons to prefer FPD over MPD (we haven't found any evidence of specific materials that perform this function in the brain, and David Chalmer's "fading qualia" and "dancing qualia" thought experiments STRONGLY indicate that consciousness must be found in the functional aspects of the brain, not in its material properties), it seems that we should all now prefer FPD over MPD.

This observation doesn't say much about the continuing debate between Representational Functionalism (RF) and FPD, (where I strongly prefer RF for reasons related to the epiphenomenalism argument). However, it does indicate that MPD should largely be removed from consideration as a potential solution to the problem of consciousness. The remaining debate must largely be between Functional Property Dualism and Representational Functionalism.