consciousness, information theory, and brain bugsFri 04 January 2013 — filed under logic Tweet
John Searle, who I respect greatly, and once had the fortune to hear speak when I was an undergraduate at Northwestern, has a review in the NYRB of Christof Koch’s new book on consciousness and reductionism. I have a few quibbles with the review.
First, I think Professor Searle is a bit too hasty when he makes a neat distinction between observer-relative and observer-independent information. He writes: “ontologically objective features like mountains and tectonic plates have an existence that is observer-independent; but marriage, property, money, and articles in the NYRB have an observer-relative existence.”
He goes on to state that “In the case of consciousness we have a domain that is ontologically subjective, but whose existence is observer-independent.” I’m not sure that the observer-independence of consciousness is as obvious as Searle would have us believe. I’m quite sure, in fact, that proving that another entity is conscious (Searle’s definition: “for any conscious state there is something that it feels like to be in that state”) is a difficult task. Searle himself illustrates this to some extent when he dismisses Koch’s example of a photodiode and his own example of a mercury thermometer: “The mercury in the glass knows nothing about temperature or anything else; it just expands or contracts in a way that we can use to gain information.”
This brings to mind our old friend the Chinese Room (which I’m so happy has its own Wikipedia page)! My aging and decaying brain struggles to dredge up the originator of this entertaining mental exercise….. was it…. Searle? Searle’s Chinese Room? If only my communicative skills were up to the task of expressing what it feels like to dimly remember an undergraduate seminar on philosophy of mind. Was I on fire for the philosophy, staying up late in caffeine-fueled blackboard sessions, struggling, struggling to begin to agree on what we were even arguing about in the first place? Were we dualists today? We weren’t yesterday. Yes, I seem to remember that. Funnily enough, I remember more keenly the kitchen of my classmate, and the sweaters she used to wear, and the pattern of the hairs on the back of her neck, and what it would have been like (and here I’m speaking of the ontologically subjective domain) to feel like we were finally speaking the same language and truly understood each other. Ah, youth.
So where was I? Yes, here in this article we have Searle taking us back to his Chinese room. This argument, which I love, is really a wonderful rhetorical appeal to intuition and prejudice, and we all should have this sort of thing in our toolbag. The move is this: (1) we agree that X has some property P, even though we don’t really understand whether or how X causes P, the relationship between X and P, or whether P even really exists. (2) we posit some other entity Y and we make it do most everything X does, albeit in some roundabout, ludicrous, or parodic way. Here is where you appeal to the prejudices and fears of your audience. Make Y really yucky. (3) We wave our hands and say “Of course, it’s just obvious that Y just isn’t the right sort of thing to have P!”
If you know me at all you know that this is where I show the clip from Starship Troopers.
Brain bugs? Frankly, I find the idea of a bug that thinks offensive!
I toyed with the idea of deconstructing various arguments against same-sex marriage here, since many seem to proceed along the same lines, but that’s a bit too digressive, and I think would be a very unfair to Professor Searle, who I really think is a good dude. Suffice to say, we can imagine the argument that straight marriages have some important property P, and we’re not sure exactly what P is or how it comes from marriages, but when we describe same-sex marriages in a particular way, it sure seems obvious to a lot of people that they don’t have P. Even though we still can’t say what P is. Or why P should make a public policy difference.
I think this entitles us to say, oh well, nothing is new here. We don’t know what consciousness is, or how it arises from brains, or if it does, or anything, really, other than some correlations between brain activity and the reports of those brains (that we have to take on faith, since we can’t verity them) that there’s something that it’s like to have that activity. But Searle can say with confidence that there’s nothing that it’s like to be a diode. Okay.
So Searle seems to commit himself to both the idea that consciousness can be identified as an observer-independent phenomenon (that other human beings have consciousness is a brute fact about the universe, like tectonic plates or mountains) and to the position that information can’t exist without an observer. It’s difficult for me to figure out, from his review, what his reasoning is, but I’m sure it’s grand.
I also think Searle goes wrong when he asserts that the information of mathematical information theory is observer-relative. I don’t think that’s right, and I’m basing that on having failed a graduate-level physics class in thermodynamics and information theory as an undergraduate. There was a lot of math going on in that class, and I didn’t understand much, if any, of what was going on around me, but it was pretty clear to me that the information content of various systems didn’t depend in the least on some observer being present to assign semantic value to the information. I’m pretty sure that the informational facts of various physical systems could be assessed, even without observing the system. Although, I freely admit, I understood very little of that class.
All in all, though, Searle makes me want to read the book. A defense of panpsychism? Sign me up!