physicalism

The Supposed Explanatory Power of the Computational Theory of Mind

The computational theory of mind was brought up in a response to my other post on physicalism. This is a view that I personally believe can be utterly devastated by even a cursory examination through analytic philosophy.

The Computational Theory of Mind (CTM) essentially states that the mind can be likened unto a computer. This view is also known as the software view of Functionalism. It is the belief that the mind is essentially a computer program. Inputs are fed in, outputs are fed, well, out. The mind can be exhaustively described in these kind of relations. Sensory inputs, behavioral outputs, etc.

This is yet another way for atheists to try to escape the nasty mind-body problem.

There are several objections that can be raised against this view. The first is that the Functionalist/CTM view focuses on defining mental states through causal relations such as the outputs of behavior rather than the internal traits of the mental state itself. In other words, Functionalists could see two mental states as identical when they are not. An example could be the classic problem in philosophy about color.

Suppose Bob and Sally enter a room with various objects scattered about and they are told to find all the objects which are green and put them in a pile. Internally, Sally is able to sense color normally, but Bob is not. However, because they are both supposed to be in the state of sensing greenness, they are both functionally in the same mental state. But Bob senses all green objects as red, and all red objects as green. Therefore, internally, he and Sally are in different mental states, but because they sort the objects in the same way (Bob has always seen green as red, so when told to sort green objects, he picks out those which are red to him), they are in the same mental state according to functionalism.

Analytically, the problem is then that CTM/Functionalism would state that:

If there are two persons who have input x=> output B, then they are in the same mental state.

But it misses the possibility that input x could be A for person 1 but culd be C for person 2.

Thus, Functionalism would state that A and C are identical, despite the fact that they are not, because it has no way of  explaining the inverted qualia (specific experiential qualities).

Further, there is the classic Chinese Room example given by John Searle in “Minds, Brains, and Science.” Summed up, the Chinese Room states that one who has no understanding of Chinese could be in a room in which inputs are given in the form of Chinese characters on sheets of paper. This person has access to a book that gives appropriate responses to these Chinese characters. He or she then selects the appropriate response, enscribes it onto a sheet of paper, and puts it through the output slot. Now suppose the rulebook is so accurate that it can make it seem as though the person always has appropriate, even perfect responses to questions, small talk, etc. in Chinese. The person could then emulate entirely the ability to speak Chinese despite having absolutely no understanding of Chinese whatsoever.

This problem comes up within CTM/Functionalism because it discounts anything but the inputs and outputs. Functionalism/CTM would have to state that this person does literally understand Chinese, but that isn’t the case.

There are, as always, more ways to tear down CTM/Functionalism, but I believe that is good enough for now. As an alternative to dualism, CTM/Functionalism lacks utterly any explanatory power in terms of internalization, inverted qualia, and absent qualia. Adherents to CTM or Functionalism believe that it has better explanatory power. This is false.

Dualism, on the other hand, has explanatory power in terms of all of these. The acknowledgement of a mind that has understanding, direct access to inverted qualia, and can sort through actual mental states, so Dualism does not fail in the sense of absent qualia.

John Searle states it well, “Earlier materialists argued that there aren’t any such things as separate mental phenomena, because mental phenomena are identical with brain states. More recent materialists argue that there aren’t any such things as separate mental phenomena because they are not identical with brain states. I find this pattern very revealing, and what it reveals is an urge to get rid of mental phenomena at any cost.”

Moreland, J.P. & William Lane Craig. “Philosophical Foundations for a Christian Worldview.”Intervarsity Press.2003.

Physicalism: Does it really have explanatory power?

Physicalism–the view that the human body is wholly physical–claims to have better explanatory power (and indeed, the only explanatory power) than other world views. Is this really true?

One way to defeat such a claim is to show that physcalism does not actually have such a monopoly on explanatory power. I believe that dualism offers just such a defeater:

The main argument I have against physicalism (and hence, for dualism) is that there are things in existence that physicalism cannot account for. These things include, but are not limited to:

1) There is causation. Physicalism essentially seems to claim that a thought or an idea, an emotion, is identical to the cause. In other words, touching part of the brain with an electrode, which triggers a sensation, IS the sensation. What physicalism then states is that things are not responses to emotions, they just are the emotion. But that is seemingly false, for all that is proven is that the mind is causally connected to the brain, not that they are identical. There is no part of the brain, for example, that is a memory. It may be shown that one can cause a memory to occur with stimulation, but that only proves that some memory (B) is caused by some firing of a neuron (A). But A is not B.

Take, for example, the idea within physicalism that love is the chemical reactions and neurological firings in the brain: love (B) is caused by chemicals (A). To say that the chemical is love is not true, for a chemical is ontologically different from an emotion—consider this example: if I conceive of a pink elephant, does that mean that whatever neurons need to fire in order to bring that thought into my brain are indeed a pink elephant (Moreland, 234)? Or do they merely cause the image of a pink elephant to appear? Likewise with any real object or imagining. These things are not physically contained in our brain, nor are they actually the chemicals or neurons themselves, they can simply be caused by such mechanical things. That does not make them identical. A may cause B, but A is not B.

2) Self-presenting properties. There are things that present themselves directly to the subject, and are considered wholly mental in nature. Things like love, the experience of red, thinking that three is an odd number—these things are directly present to a subject because that subject has them immediately in his/her field of consciousness. Two evidences exist for these properties: the first is that one can have private access to mental properties, but not physical properties… and the second is that one can know at least some of one’s own mental properties incorrigibly. People can know things themselves that they cannot be wrong about. In other words, I can know without question what the color green appears to be to me. No one else can know that.

3) The subjective nature of experience. This is called the “knowledge argument.”  This one is something that is hard to explain without using an example (ty to J.P. Moreland for this). Suppose there is a deaf scientist who is the single leading expert on the neurology of hearing. It would be possible for him to know and describe everything involved in the physical aspects of hearing… yet not actually have knowledge of hearing itself. This experience is essential and subjective. It is also outside of the realm of physicalism to explain.

4) Intentionality. We can have an ‘ofness’ or ‘aboutness’ with our action that is inexplicable through physical needs. “Mental states have a directness that is intrinsic to them (Moreland 237).” In other words, many mental states are of or about something: fear of something, thoughts about something, etc. Now, there doesn’t seem to be any way to reduce something such as a thought about something to a physical explanation. In other words, the ‘aboutness’ of a thought defies physical explanation.

These are just a few arguments against physicalism. There are a couple more that could be made, but that would make this longer than I think it needs to be. Further, each individual kind of physicalism is subject to a wide array of critiques.
Moreland, J.P. & William Lane Craig. “Philosophical Foundations for a Christian Worldview.”