Saturday, September 3, 2011

Aristotle's Revenge

Eliminative Materialism

Eliminative materialism seeks to “eliminate” the mind entirely, by denying qualia, or intentionality (the ability of something to be about something other than itself), or propositional attitudes (belief that x, hope that x, desire that x, etc). This follows necessarily from the modern version of materialism, which denies Aristotelian formal and final causes and only embraces material and efficient causes. If everything is just particles and forces bumping around (just material and efficient causes), then on this view there can be no mind because there can be no intentionality (pointing to something beyond itself). So EM says that beliefs, desires, and so forth do not exist and will be replaced by neuroscientific concepts: “activation of sodium ions in xyz dendrites”, and so forth.

It is important to note that this theory does not say that “activation of sodium ions in dendrites” is the cause of beliefs and desires (which would be trivial), but that there are no such things as beliefs and desires and so forth, there is only the neuroscientific facts.

One problem with this is that it does not involve replacement of the mind with successor concepts, but rather just examples of inference, metonymy, and semantic shift. You can infer smoke from fire, but you have not replaced the smoke with fire. When Barak Obama speaks, you can refer to him as “Washington” (a metonym) but you have not replaced Obama with Washington.

EM theories of mind destroy reason and science, because both of those terms require intentionality and mind to function. Few materialists are eliminative materialists for this reason. However, if final and formal causes are rejected, then it is hard to see how there could be any other result than eliminative materialism. The mind, in pointing beyond itself as it does when it develops theories, and reasons, is an example of final causality.

Materialist Theory of Mind

The main materialist theories of mind state that the mind is a sort of software, running on the hardware of the brain. The program contains symbols that represent the world and are manipulated via algorithms. But there are many problems with this view.

1. Symbols: If everything is just particles bumping around, then nothing counts as a symbol unless some mind interprets it as such. Particles arranged in the form of a picture of the world can only count as a symbol of the world if some mind interprets it that way. Apart from an interpretive mind, the particles arranged in a picture of the world are just meaningless particles. Since the materialist account of the mind is that thought is a symbol in the software in the brain, but nothing material can be a symbol without an interpretive mind, then this theory loops back around to mind and is not successful in reducing mind to matter.

2. Algorithms: Similarly, nothing counts as a “program” or an “algorithm” unless some mind interprets it as such. I follow an algorithm to move around a desk, and a marble also rolls around a desk due to an earthquake, only I can be said to be following an algorithm. The marble, being unconscious, is not. For something to be a “program” requires a mind, then similarly this theory is similarly circular like above.

3. Representation: It is theorized that for something to be a symbol requires it to be associated with something for awhile. If A is constantly associated with B, then A comes to symbolize B. But the problem is that the causal chain from A to B extends beyond these two in both directions. The sunlight, hitting the snake, going to eyes, going into brain, brain event, a linked brain event, etc. It takes a mind to decide that A and B are the begin and end points. Thus, also circular.

4. Meaning: For the mind to process a logical deduction, the mind performs a calculation like a calculator. The calculator input takes 1 + 2 and then gives back the symbol 3. However, the accuracy of this entirely depends on someone interpreting the symbols to represent “1” and “+” and “2”. If we instead interpret the 1 symbol to actually mean “3”, and the 2 symbol to actually mean “4”, then the calculator will give nonsensical answers. I.e., without us around to interpret the symbols correctly, the calculator is not actually adding or subtracting or doing anything coherent at all. Similarly, materialism of the mind aims to have the logical thought process as an unconscious manipulation of symbols, but like the calculator, without a mind around to add (coherent) meaning to these symbols, the mind can’t be doing anything coherent at all. And once again, mind is needed to be brought in to explain mind, and the materialist reduction is unsuccessful.

Aristotelian Teleology

However, if formal and final causes exist in nature, then the above materialist theories of mind would not be a problem. If you have inherent tendency for things to point to something beyond themselves, then you could appeal to unconscious symbols, programs and so forth in nature to account for mind. If you have formal causes, then the intellect can contain these universal forms and give us knowledge about the world. The above theories would then be perfectly intelligible.

Dualism of the mind is a byproduct of the rejection of formal and final causes. Since the mind is the clearest case of these, it becomes necessary then to postulate another mysterious substance that is not material. If you want to avoid eliminative materialism but keep the mind, dualism follows necessarily. To avoid both, it is necessary to bring back formal and final causes.

The mind is where materialists dump everything that does not fit the mechanistic picture of the world (devoid of formal and final causes). This is why the mind will continue to resist materialist reduction. It is like cleaning a house by sweeping all the dirt in it under a single rug, and then claiming you are going to get rid of the rug in the same way.

Irreducible Teleology

1. Biology: Evolutionary biology is laden with teleological terminology: the heart is for pumping blood, the liver is for purifying blood, sex is pleasurable so that we procreate, etc. Since final causes are out, then these have to be eliminated some how. Philosophers of science have proposed a few ways of doing this.

One way is to simply reword them as efficient causes. “The heart’s purpose is to pump blood” really means “ancestors of this creature who had proto-hearts survived in greater numbers than their neighbors, passing along the genes for hearts, which became more complex over time because those who had more complex hearts survived in greater numbers... etc”.

This is a problem because it seeks to explain final causes as “really” just a kind of efficient cause. But final causes are not efficient causes, and so this is a pointless exercise, like trying to explain how an apple is really just a kind of orange. It also leads to absurdities. It suggests that we can’t know what something is for unless we know its evolutionary history. But consider swampman. Swampman was created when lightning struck a puddle of mud. He is physically identical to humans. In his case, though, we can’t say that his heart is for pumping blood because his heart did not evolve. We can’t say it does anything. This is clearly absurd.

John Searle says that reducing final causes to efficient causes is a pointless exercise, because evolution isn’t supposed to be about teleology at all. Teleology should not be reduced, but eliminated. So the above exercise in explaining teleology is really an exercise in eliminating it.

However, eliminating teleology is impossible. Eliminating it in one place just makes it pop up somewhere else. Even in John Searle’s own proposal, which is to eliminate teleology by saying that it is in our minds, where we assign a normative value to the causal process. But “assigning a normative value” is itself goal-directedness, or teleology, and so this has just shifted the location of teleology without getting rid of it.

Daniel Dennet says that the functions of bodily organs and so forth are not there intrinsically either, but instead of saying that it is in our minds, he says that it is the result of the “purposes” and “goals” of natural selection. But if he is serious, then he is embracing Aristotle’s final causes. If it is just a figure of speech, then it has no explanatory power at all.

What he might mean is what he calls the “intentional stance.” We act as if the burglar alarm “knows” we are home. We act as if the fire alarm “knows” there is a fire. Similarly, Dennet says, we act as if nature has unconscious goals or purposes. But if this is just in his own mind, then it has no explanatory power at all. If it’s something in reality, then he is talking about unconscious final causes (Aristotelian teleology) and thus he is abandoning his naturalism. If he says that our intentional stance derives from natural selection, but natural selection derives its intentionality from our mind, then he is going around in a circle. Dennet is ambiguous as to what he means, and this rhetorical sleight of hand is what gives his position any plausibility at all.

Finally, teleology is most often relocated to DNA, which consists of “blueprints” and “algorithms” and the like. Dawkins speaks of genes being “selfish”. Etc. But as above, in a world of just particles, nothing can count as a symbol unless some mind interprets it that way. Yet DNA contains blueprints for lifeforms, and so “points to” or “aims at” something beyond itself, even though there is no mind interpreting it that way. It is an unconscious symbol. This is Arisotle’s final causes. Removing this unconscious teleology from DNA strips it of all the explanatory power that it has in biology.

2. Non-organic cycles

There are certain causal chains that have significance that others do not. The causal chain that begins with a cat and ends with a certain brain state is significant in a way that the causal chain that begins with the fur of the cat and ends six inches in front of our eyes is not.

There is teleology in the water and rock cycles as well. Water evaporates, condensation occurs, rains happens, and the cycle starts again. Igneous rock forms, then metamorphic, which melts into magma, and the cycle begins again.

It won't do to frame these in efficient causes only. The magma may cause bird migrations. Sediment may block water flow to a region. Condensation may cause arthritis. But each of these things are inherently directed towards a specific effect that is in their nature. Condensation may be the efficient cause of arthritis, but it is in it's nature directed at the specific effect of causing rain. That is what it inherently points to.

3. Laws of Nature

The modern conception of the laws of nature are inherited from Hume. Since final causes (inherent powers) cannot be observed or empirically verified, therefore they either do not exist or we cannot know about them. So to say that X regularly causes Y is just to say that there is a law like regularity between the two, but no inherent or necessary connection. Science is in the business of uncovering these law-like regularities.

But this does not seem right. Science always talks about idealizations, like frictionless surfaces, that are never actually realized. Science extrapolates these from a few experiments. It seems to be in the business of uncovering the hidden powers of things, not just a law-like regularity. If it were finding law-like regularity, then it would have to observe multiple instances of this and infer via induction that it holds everywhere. But on a Humean account, since there are no inherent powers or final causes, induction becomes impossible to justify.

Some (otherwise non-theistic) philosophers of science agree with this view, which they call “new essentialism.” That there are inherent powers in things, directed towards specific effects. This is, of course, nothing less than Aristotelian final causality.

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