Sunday, December 11, 2011


Some Philosophy

There's a couple of interesting philosophical discussions online.

Massimo Pigliucci takes on the idea that consciousness is an illusion in "You don't really exist, do you?":

One more thing strikes me as strange from the point of view of the "consciousness is an illusion" school of thought. Its supporters have no account of why this illusion would evolve. If we take seriously the commonsensical idea that consciousness aids deliberative reasoning, then we see that it has a (important) biological function. But if it is just an illusion, what's it for? Now, as a biologist I am perfectly aware that sometimes in evolution shit just happens ("spandrels," as Stephen Gould and Richard Lewontin referred to structures that seem adaptive but are in fact byproducts of evolution). But if a large amount of metabolic energy used up by the brain goes into maintaining the illusion of consciousness surely one wants an answer to the question of why did natural selection bring this situation about or — if consciousness is a spandrel — why does it persist in the face of what should be strong selection against it. We know that when organisms don't need complex structures/functions natural selection quickly eliminates them (for instance, in the case of eyes for cave animals).
Somewhat related is Stephen Law's article, "Naturalism, evolution and true belief," on Alvin Plantinga's Evolutionary Argument Against Naturalism:

Plantinga supposes that what unguided evolution favours, in the first instance, is adaptive behaviour. As to what causes that behaviour, evolution doesn't care. True beliefs, false beliefs, something else – it's all the same to evolution. It is only the result – adaptive behaviour – that is preferred. ...

Consider the suggestion that there exist certain conceptual constraints ["CC"] on what content a given belief can, or is likely to, have given its causal relationships to, among other things, behaviour. ...

[G]iven such conceptual constraints exist, unguided evolution will indeed favour true belief. Consider our thirsty human. He has a strong desire for water. He'll survive only if he walks five miles south to where the only reachable water is located. He does so and survives. Suppose this adaptive behaviour is caused by a certain belief/neural structure. If there are conceptual constraints on belief content of the sort I envisage, and if a belief/neural structure in that situation typically causes subjects to walk five miles south, then it is quite likely to have the content that there's water five miles south – a true belief. Were our thirsty human to head off north, on the other hand, as a result of his having a belief/neural structure that, in that situation, typically causes subjects to walk five miles north, then it's rather more likely that the belief in question is that there's water five miles north. That's a false belief. Because it is false, our human will die.
Have fun.

Not sure about the word "illusion" in this context. If you experience an optical illusion, it presupposes that you are conscious of it, and ditto for any experience. To call consciousness itself an illusion seems circular. In any case, Massimo is jumping the gun. Before one can use evolution to explain the "illusion", one must first show how it can exist under known physics. Build a computational or biological system and prove that it is conscious
My main complaint with Plantinga is that he begins by assuming that beliefs just swing free from behavior. Once this Cartesian assumption is granted, all he needs is some clever thought experiments to show that the causal link between beliefs and behaviors cannot be necessary. A quite different approach would be generated, I think, if one were to begin by thinking about beliefs as dispositions to behave in specific ways under specific circumstances.
If a certain belief/neural structure said that water was five miles to the south because ice demons lived five miles to the north and those demons always live 10 miles to the north of water, then evolutionary processes in Law's example would tend to reinforce that belief as "true."
Two thirsty men stand in a plain. In the distance, five miles to the north, there are snow capped mountains. To south, more hot and dry plains.

One man says he's going north to find water, because where there's snow there will be streams fed by runoff.

The other man is going south because he thinks he saw a pretty woman that way and, while he's thirsty, he mostly wants sex. And, oh yeah! Maybe that woman will have water.

The other man knows his friend always has sex on the mind, and so chooses to go north. He's right, there is water there, but before he reaches it he falls in a crevice and breaks his leg. Because he's alone, there's no one to help him and so he dies.

The other man goes south, doesn't find that girl but does find water and so he lives and eventually finds another woman.

Evolutionarily speaking, this is the reason for "Two and a Half Men."
"In any case, Massimo is jumping the gun. Before one can use evolution to explain the 'illusion', ..."

I think you misunderstand Massimo's point. He's not defending the notion that consciousness is an illusion, he's challenging it.

And TB, while you can come up with scenarios where false beliefs luckily lead to true beliefs or useful results, I think you'd be hard-pressed to find a plausible scenario where one can consistently be wrong about where to find food, shelter, mates, etc., and still survive. Evolution certainly can favor quick-and-dirty heuristics over slower and more correct deliberation, but if one's beliefs don't have at least a family resemblance to reality, one is at a disadvantage that is most likely fatal.
I think you misunderstand Massimo's point. He's not defending the notion that consciousness is an illusion, he's challenging it.

I understand that, but my point is that before evolution can be relevant, consciousness must be shown to have a physical basis for selection to act upon. Positive, negative, or neutral.
Hi JJ!

I agree with your point about someone being consistently wrong.
But one doesn't have to be consistently right or wrong, they just need to be lucky enough times to survive and go on to succesfully reproduce. And I don't think it would be too difficult to find that plausible scenario you describe - I would start my search by turning on "Jerry Springer."
My other point is that my stories and Law's story are just that - stories. Like theoretical physics, they can be true and correct by themselves, but that doesn't prove they accurately reflect reality.
Except that sitcom thing - that's absolutely true.
I should note that I'm not defending Plantinga against Law here, as much as I'm expressing my distrust of storytelling that's used to make a point. And I've been that way ever since "24" affected the debate on torture.
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