Saturday, August 25, 2012

 

Nageling Doubts


Okay, the Discoveryless Institute has been trumpeting Thomas Nagel's new book, Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False ... particularly because of this quote:

In thinking about these questions I have been stimulated by criticisms of the prevailing scientific world picture... by the defenders of intelligent design. Even though writers like Michael Behe and Stephen Meyer are motivated at least in part by their religious beliefs, the empirical arguments they offer against the likelihood that the origin of life and its evolutionary history can be fully explained by physics and chemistry are of great interest in themselves. Another skeptic, David Berlinski, has brought out these problems vividly without reference to the design inference. Even if one is not drawn to the alternative of an explanation by the actions of a designer, the problems that these iconoclasts pose for the orthodox scientific consensus should be taken seriously. They do not deserve the scorn with which they are commonly met. It is manifestly unfair.
So I bought the Kindle version for $13.72 US. I've read about a third of it and it already seems like a waste of money.

As far as the above quote goes [see P.S. below!], Nagel does state that "[p]ointing out [the limits of the tools of science] is a philosophical task ... rather than part of the internal pursuit of science ...". Which is what we have been saying about ID for as long as it has been claiming to be "science." In a class on the philosophy of science, it is fine (if outmoded and rather silly). However, it and its supposed "controversy" has no place in a science class.

Nagel's objections to materialism (which he seems, to my "mind," to naively equate with science) are:

[T]here are doubts about whether the reality of such features of our world as consciousness, intentionality, meaning, purpose, thought, and value can be accommodated in a universe consisting at the most basic level only of physical facts— facts, however sophisticated, of the kind revealed by the physical sciences.
Nagel has not, up to the point I've read, put forth a simple, clearly delineated, explanation of his argument. Instead, he has argued against several schools of thought about "mind" and science. Anyway, here is his premise, as much as I can gather:

[W]hat explains the existence of organisms like us must also explain the existence of mind. But if the mental is not itself merely physical, it cannot be fully explained by physical science. And then, as I shall argue, it is difficult to avoid the conclusion that those aspects of our physical constitution that bring with them the mental cannot be fully explained by physical science either. If evolutionary biology is a physical theory— as it is generally taken to be— then it cannot account for the appearance of consciousness and of other phenomena that are not physically reducible. So if mind is a product of biological evolution— if organisms with mental life are not miraculous anomalies but an integral part of nature— then biology cannot be a purely physical science.
The crux of Nagel's argument concerning consciousness is this:

It is certainly true that mental phenomena have behavioral manifestations, which supply our main evidence for them in other creatures. Yet all these theories seem insufficient as analyses of the mental because they leave out something essential that lies beyond the externally observable grounds for attributing mental states to others, namely, the aspect of mental phenomena that is evident from the first-person, inner point of view of the conscious subject: for example, the way sugar tastes to you or the way red looks or anger feels, each of which seems to be something more than the behavioral responses and discriminatory capacities that these experiences explain. Behaviorism leaves out the inner mental state itself. ...

What is it about [a physical event in the central nervous system] that makes it also [a mental event like pain or a taste sensation]? It must be some property conceptually distinct from the physical properties that define [the physical event in the central nervous system]. That is required for the identity to be a scientific and not a conceptual truth. ...

But all such strategies are unsatisfactory for the same old reason: even with the brain added to the picture, they clearly leave out something essential, without which there would be no mind. And what they leave out is just what was deliberately left out of the physical world by Descartes and Galileo in order to form the modern concept of the physical, namely, subjective appearances. ...

So if [a mental event like pain or a taste sensation] really is [a physical event in the central nervous system] ... then [a physical event in the central nervous system] by itself, once its physical properties are understood, should likewise be sufficient for the taste of sugar, the feeling of pain, or whatever it is supposed to be identical with. But it doesn't seem to be. It seems conceivable, for any [physical event in the central nervous system] that there should be [a physical event in the central nervous system] without any experience at all. Experience of taste seems to be something extra, contingently related to the brain state— something produced rather than constituted by the brain state. So it cannot be identical to the brain state in the way that water is identical to H2O.
Somehow, in some way, that Nagel does not explain clearly, those arguments metamorphize into:

I believe we will have to leave materialism behind. Conscious subjects and their mental lives are inescapable components of reality not describable by the physical sciences.
Huh? If you are experiencing the taste of sugar, I can guarantee to stop that sensation by putting a bullet in your brain ... or, less drastically, by shooting you with a tranquilizer dart. What's more, by using a fMRI or EEG, I can show that there was a physical difference in your "brain state," before and after, that corresponded to the cessation of the "subjective appearances" of sweetness. Indeed, if the "subjective appearances" of pain are not physical states, why do we have people called anesthesiologists? And don't forget the "God helmet."

Do these examples prove conclusively that "mind" is simply a state of the brain? No. But vaguely stating that something is a "subjective appearance" does nothing to show that they are anything distinct and separate from brain states. They are clearly linked and until and unless Nagel can give good reasons to state otherwise, his is just a "mind in the gaps" argument.

I would have bet that Nagel was not stupid, even if wrong in this regard. But he trots out the old quote mine of Richard Lewontin, well explained here.

I guess I'll have to recalibrate.

________________________________

P.S. I should have mentioned the usage of ellipses by creationists. In the "quote" by the DI of Nagel, they start:

In thinking about these questions I have been stimulated by criticisms of the prevailing scientific world picture... by the defenders of intelligent design.
What's in that ellipsis? Why, this:

In thinking about these questions I have been stimulated by criticisms of the prevailing scientific world picture from a very different direction: the attack on Darwinism mounted in recent years from a religious perspective by the defenders of intelligent design.
There is always one thing you can count on with the Discovery [sic] Institute ... dishonesty!

Comments:
Maybe this will help. Nagel accepts an argument previously developed by Saul Kripke (in Naming and Necessity), and which has been developed also by David Chalmers. The that runs as follows:

(1) identity is a necessary relation (i.e. if x and y are identical, then they are necessarily identical).

(2) if it is conceivable that something can be an x without also being a y, then it is possible that something can be an x without being a y.

(3) If it is possible that something can be x without being y, then it cannot be necessary that everything that is an x is also a y.

(4) hence, if it conceivable that a being can display all the behaviors associated with consciousness and yet actually lack consciousness, then such a being is possible.

(5) and if such a being is possible, then there is no necessary relationship between physical states and mental states;

(6) and so mental states cannot be identical with physical states
 
Yeah, I saw that in the book ... he cited Kripke (and I'll have to go back and read that, which I am pretty sure I have). The problem is, as I see it, the fact that something is conceiveably different says little or nothing about whether it is true. We could conceiveably have a universe without quantum mechanics. That says nothing about whether quantum mechanics is true and whether we have evidence it is true. Nor is there any requirement I can see that things must be "necessarily identical" in order for them to be both identical and true.

Now I should say I am sympathetic to Nagel's view that science is underdetermined in the sense of Justified True Belief, but that is no good [cough] reason to posit that there is something called "mind" that is different than "brain states." It's not that I am adverse to evidence of that, its that I am adverse to (as far as I've seen so far) unevidenced assertions of it.
 
P.S.

(5) and if such a being is possible, then there is no necessary relationship between physical states and mental states;

(6) and so mental states cannot be identical with physical states


That's the thing I can't see as following logically. Just because it is not "necessary" (and I don't "necessarily" agree that he has established that) that physical states and mental states are identical, I don't see how that establishes that they aren't identical, much less that the cannot be identical. Maybe I'm missing something ...
 
Nagel has been making this sort of argument, at least since 1974 when he wrote "What is it like to be a bat?" The SEP entry Qualia: The Knowledge Argument indicates that the style of argument is a lot older.

I did read Nagel's bat argument. I don't like his writing style at all, so I won't be buying his latest book. Nagel's writing style is perhaps typical of what turns scientists off philosophy. And it doesn't have to be that way. Frank Jackson's version of the knowledge argument (also mentioned in that SEP entry) is in a style far more congenial to scientists, though no more persuasive than Nagel's argument.

I'm not sure whether Nagel is a dualist. Frank Jackson was (he has since recanted).
 
Nagel has been making this sort of argument, at least since 1974 ...

This is, except for his 2009 attempt to shill for the IDers, the first time that I've paid any attention to Nagel.

Although I didn't mention it (I may do other posts about this), I was rather surprised that Nagel favorably invoked Plantinga's evolutionary argument against naturalism. Umm ... Plantinga's argument that belief in God rescues science from incoherence is not very convincing but what the heck Nagel thinks rescues science in a non-theistic world I have yet to reach. But hints so far is that it is some sort of universal intelligence. Deepak Chopra anyone?
 
That's the thing I can't see as following logically. Just because it is not "necessary" (and I don't "necessarily" agree that he has established that) that physical states and mental states are identical, I don't see how that establishes that they aren't identical, much less that the cannot be identical. Maybe I'm missing something ..

What I think you're missing is the force of the very first, Kripkean premise -- that identity is a necessary relation.

If we begin with that premise -- that identity is a necessary relation -- then if two things are identical, they are necessarily identical (meaning, in philosophy-speak, "identical across all logically possible worlds").

Since the bar for identity has been set extremely high, all it takes is one logically possible world in which those properties are separate for it to be the case that we don't have logical necessity, and hence, we don't have identity, either.

One might wonder whether it really makes sense to raise the bar for identity-conditions that high. I don't fully understand Kripke's argument there myself. That said, I think there are some philosophically attractive options for resisting dualism even if Kripke's argument against crude physicalism is accepted.

(It's been a while since I've looked at this stuff too much, and the metaphysics of mind is not my specialty.)

I agree with you both about the connection between Plantinga and Nagel and also what is problematic about them. I regard Plantinga's EAAN as quite problematic for roughly the same reason as Nagel's anti-physicalism. The EAAN rests on the same move, from conceivability to possibility, and from possibility to the denial of necessity. That doesn't get you very far, because it only gets you to the denial of a priori claims. It doesn't say anything about what is reasonable to believe on the preponderance of available evidence.

(That Nagel favorably invokes Plantinga's argument doesn't surprise me at all. Both of them are, I think it is fair to say, following through on Kripke's trail-blazing rejection of naturalism and resurrection of a priori metaphysics.)
 
OK, that at least makes their argument clearer, if not anymore convincing. It reminds me a bit of the ontological argument ... from conceivability to possibility, and from possibility to existence.
 
Yes, it's a bit like that. Not as hocus-pocus, hey-Rocky-watch-me-pull-a-rabbit-out-of-my-hat as Anselm's ontological argument, but similar. In both cases, the crucial move is from conceivability (which is about human cognitive powers) to possibility (which is a metaphysical category). If one begins from the premise that it is possible that there is a necessary being, the rest is trivial. It's getting to that premise, or showing that one is entitled to it, which is much, much harder.
 
hey-Rocky-watch-me-pull-a-rabbit-out-of-my-hat

I love technical philosophical terminology!

;-)
 
"That trick never works!" -- Rocky
 
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