Professor DeLong has grepped Professor Nagel’s Mind and Cosmos for “common sense” and pulled out four quotations, presented here: [sadly, I only have the dead-tree version of the book, so I couldn’t find page numbers for all of the cites]
- But it seems to me that, as it is usually presented, the current orthodoxy about the cosmic order is the product of governing assumptions that are unsupported, and that it flies in the face of common sense… [p. 5]
- My skepticism is… just a belief that the available scientific evidence, in spite of the consensus of scientific opinion, does not… rationally require us to subordinate the incredulity of common sense…
- Everything we believe, even the most far-reaching cosmological theories, has to be based ultimately on common sense, and on what is plainly undeniable… [p. 29]
- I have argued patiently against the prevailing form of naturalism, a reductive materialism that purports to capture life and mind through its neo-Darwinian extension… I find this view antecedently unbelievable— a heroic triumph of ideological theory over common sense…
Were I a less charitable reader of both DeLong and Nagel, I might at this juncture point out the very contested relationship between economics, philosophy, and “common sense”. I think it’s very unfair to say that the snowball fight of both disciplines begins by pelting the inhabitants of the fort of common sense with counter-intuitive snowballs of jargon. Were I less suffused with Christmas spirit, I’d narrate how, upon capturing the fort, the ruddy-cheeked victors announce that the coalition forces arrayed against “common-sense” were actually defending positions whose correctness ought to be obvious, and that those scruffy kids down the hill are talking a lot of nonsense and also maybe loading up their snowballs with rocks.
Which is to say, when academics are arguing for or against common sense, my finely-honed legal mind allows me to recognize that the learned counsel is attempting to sway the jury, either by appealing to their innate good sense and reasonableness (“Are you going to listen to that big-city lawyer or to what we know is right in our hearts?”) or to their savvy and sophistication (“Don’t be charmed by that homespun act, you and I both know the world is more complicated than he’d have you believe!”)
Having said all that, of course I’m unqualified to comment on Professor DeLong’s ongoing (one-sided?) tussle with Professor Nagel’s book. This won’t stop me, after all, I have been reading DeLong’s blog for years, and I read Nagel in college, and I even carried his latest slim volume around in my briefcase for several weeks. Clearly I can wade right in.
So, DeLong, I think, is making the point that of course we need to subordinate our common sense to scientific theories. And we wouldn?t expect any less from him, as he is, of course, a scientist — just look at all of those graphs on his blog. And he quotes from a quantum mechanics text which uses the word “eigenvectors”. Which, since I took both Math C-92 (Vector Calculus) and Philosophy B-20 (Science and Human Culture), I know very well means “go away, you’re not a real scientist”.
[Okay, maybe my good cheer is wearing off a little bit, but it’s still a bit too early for the Glögg I need to keep it going, day after day, under this gray sky.]
Since he is a man of science, DeLong’s reading Nagel looking for bad science. And yeah, there’s some in there. I’m not sure Nagel’s quixotic tilt with evolution makes sense in the context of his larger campaign. Actually, I’m pretty sure everyone here thinks they’re Sancho Panza. Somebody’s got the wrong idea about those windmills (for Nagel, it’s scientists, and for DeLong it’s Nagel) and anyway that horse (reductionistic materialism, for Nagel) is a mule (infertile, which is to say, won’t produce results which “explain” anything). [Hey, that almost worked!]
Where Nagel’s book is weakest is where he attacks or appears to attack methodological naturalism, especially in the context of evolution. This is not a good avenue for him, and it puts him in bad company, and think it was unwise to head down that path, especially since it makes really smart guys like DeLong forget their Christmas cheer.
Nagel would have better luck talking to smart scientists like DeLong if he talked more about models, I think. “Look,” he’d say, in my imaginary dialogue, “naturalism is a very successful model which has helped us make fantastic strides in understanding the world. That the physical universe is causally closed, and that everything we observe results from the interaction of particles and fundamental forces, and that everything proceeds according to regular rules that we can derive from repeated observations — that’s been a really really good assumption. Right? Right.”
And I think what Nagel wants to focus on is noting that we assumed it as a starting point, and maybe he could use some help from a historian of science, or whoever. And maybe it helps that it is, or was, counterintuitive. After all, it’s not as if it’s obvious that the physical universe is causally closed, or that “physical universe” is even something that can be easily unpacked and explained to even the smartest guys from X years ago.
So, (a) it is (or was) an assumption, and (b) it’s been working great. (c) is that when we run into stuff that doesn’t fit (and for Nagel this includes consciousness, objective morality, and the ability to reason about objective reality) we need to say one of several things:
1. This thing you think you found that doesn’t fit the model? Yeah, if it doesn’t fit the model, it’s not a real thing, it just doesn’t exist. It’s like a phantom or a rogue bit of folk wisdom, and we know it’s counterintuitive, but you just gotta get over it.
2. This thing you found that doesn’t fit in the model? Yeah, the model doesn’t actually explain everything, there’s just some leftover bits about existence, and we leave those for other people to explain using some other system.
3. You found a thing that doesn’t fit in the model? For now, we’re going to concentrate on the parts of the model that work well, and maybe later, when we’re just better overall at everything, we’ll find a way to make it fit.
4.This thing you think you found that doesn’t fit the model? That old thing? Well, you actually don’t properly understand that thing, it totally does fit the model. Why don’t you read my book on that thing and when you’re done, let me know if you still think it doesn’t fit.
5. Something doesn’t fit the model, and you say it never will? Oh crap, we need to question and re-evaluate all of our underlying assumptions.
Nagel wants #5. He’s got a little list of n items and he says, hey, these are real and they don’t fit the prevailing model and moreover they will never fit the prevailing model. And he keeps saying that some of the stuff on his list is “common sense” when really what he wants to say is that they’re “properly basic”, borrowing Plantinga’s terminology (though this starts to wade into theistic waters, and Nagel’s not ready to swim there), or that they’re the sort of observations about the world that only a radical skeptic could call into question, or something else, I’m no epistemologist. If we’re at the point where neuroscientists are having to argue that we’re not actually conscious, I mean, really, come on.
What he’s also pointing out is that the model’s been lifted up to the point that modelistas refuse to recognize the possibility of real things existing that don’t fit the model. Everything must fit, and if it appears not to fit, it either actually does fit, in some way we don’t understand yet, or it doesn’t really exist. The model is no longer subject to question or revision. And this isn’t healthy. And it’s not exactly science anymore, really.