APA wrap-up: Kyle Stanford's "New Induction"

My time at the APA last weekend was pretty good: I learned a few new things, met some new people I've been wanting to meet, and got to catch up with a couple old friends. Particularly helpful/ enlightening presentations included Angela Potochnick on how the context of inquiry shapes explanation, Ken Waters (plus commenters Jay Odenbaugh and Michael Strevens) on causes that make a difference (not, I learned, to be confused with the conception of causes as 'difference-makers'), and the Author-Meets-Critics session on Kyle Stanford's Exceeding Our Grasp.

Stanford's basic claim is that current scientific theories are underdetermined -- not because we can generate empircially equivalent rivals to our currently accepted theories, but rather because at many, many times in the past, the scientific community has been unable to conceive of good alternatives to the then-current theory. The evidence that such alternatives exist is the fact that they are proposed and accepted centuries later: thus, Newton's mechanics did not consider special relativity as an alternative hypothesis; Newton's, when he proposed his gravitation theory, did not consider the general theory of relativity as an alternative; no classical physicists before 1900 considered quantum mechanics as an alternative explanation of the data, and so on. This is what Stanford calls the "New Induction" over the history of science.

The idea, as just presented, strikes me as a promising line to take. But there is one aspect of Stanford's presentation of the problem that I don't understand. Fiona Cowie asked (in part) about this in the question and answer session, but I still didn't follow the answer. Stanford says that (e.g.) in 1700, the special theory of relativity and Newtonian mechanics were "(roughly) equally well-confirmed". Similarly for the other cases: the future theory is supposedly just as confirmed as the old one -- even in the past.

I don't understand why Stanford says this for two reasons: (1) He doesn't need the theories to be equally well-confirmed for his point to hold (viz., scientists aren't even conceiving of a hypothesis that will later be accepted as superior), and (2) it seems false to me, on any reasonable (i.e., not hardcore hypothetico-deductive)notion of confirmation. In 1700, it is true that special relativity and Newtonian mechanics agreed on all the consequences that could then be observed. But someone who, in 1700, said "Newton is approximately right, yet when something goes really, really fast its length will contract and its local time will dilate from the point of view of slower-moving observers" -- there is NO evidence at all for postulating that further bit of theory. And it's the same with GTR (what evidence would there've been for gravitation being a 10-component tensor instead of a scalar?) and especially QM (what evidence was there for thinking a body cannot have a determinate position and momentum simultaneously?). In 1700, these now-accepted alternatives were consistent with the data, but they were not equally well-confirmed.

Note: a very similar line of objection is pushed at the end of P.D. Magnus's "What's New about the New Induction?" (Synthese, 2006), though he develops it slightly differently, I think. (As I understand him, P.D. claims that in 1700, STR, GTR and QM would look like 'gruesome' hypotheses.)

Off to the Pacfic APA

I'll be at the APA in San Francisco from this Wednesday til Saturday afternoon; I'm be commenting on a paper by Barry Ward on the paradox of confirmation (a.k.a. the Ravens paradox).

So if you're there, and you want to catch up/ chat/ harrass me etc., please track me down.

semantic pathology spotted in the wild

Perhaps the most famous instance of a sentence that exhibits semantic pathology is the Liar: 'This sentence is false'; if the 'this' strikes you as problematic --

(1) (1) is false.

But there are many other types of semantic pathology, such as the 'heterological' paradox and the so-called 'truth-teller': 'This sentence is true.' My colleague James Woodbridge is doing a lot of interesting research in this area; check out his work if you are interested.

This is not a serious post about semantic pathology, but rather just a field report. I sometimes wonder whether these examples like the truth-teller are all that important, since it's hard to imagine circumstances under which speakers might utter it. But I think I may have found a couple of instances of something akin to the truth-teller "in the wild":

(i) A couple of weeks ago, I went to see Spamalot, the musical adaptation of Monty Python and the Holy Grail. One of the songs contained (something close to) the following line: "This is the song that goes like this."

(ii) In the instructions for the Pennsylvania state tax forms, I found (something like) the following:

"You are eligible for the Tax Forgiveness credit if you meet the following requirements:

1. ...
2. ...
3. You meet the eligibility requirements for the Tax Forgiveness Credit.
4. ..."

Carnap on what's 'really wrong with the Aufbau'

When I was going through some of the photocopied material I have from the Rudolf Carnap archive, I found the following interesting (to me) remark. Carnap is discussing with Nelson Goodman a draft of Goodman's dissertation (A Study of Qualities, which much later became The Structure of Appearance). Goodman points out various supposed technical defects with Carnap's method of quasi-analysis presented in the Aufbau, and Carnap says roughly the following:

The real problem with my Aufbau is not the various counter-examples that can be constructed against my particular version of quasi-analysis (which I already knew about), but rather the assumption of extensionality.

(I haven't quoted, because I don't think it's allowed.) I like this because (a) it's a really smart philosopher saying 'My book rests on a mistake,' and (b) it fits with my pet theory that the real break between Carnap and Quine stems in large part from Carnap moving away from the extensional languages he espoused in Logical Syntax, while Quine held fast to the extensional standard throughout his life (see the posthumous "Confessions of a Confirmed Extensionalist").

confusion and prokaryotes

One of my recurrent interests is confusion, especially in science. The way I understand this concept is as follows: a term or concept is confused = that term or concept takes 2 or more entities to be one entity (where 'entity' covers individual objects, properties, relations, etc.). In other words, a confused concept or term conflates distinct things. I think the phenomenon of confusion is important in science because part of what happens in many scientific revolutions is that, from the point of view of the new scientific framework, the old scientific framework is confused -- or vice versa. (Re: 'vice versa': Einstein's principle of equivalence, for example, would be seen as an unjustified conflation from the viewpoint of a classical physicist: gravitation and inertia are two separate things, and running them together as Einstein does is an unjustified conflation.)

I've recently started looking at another potential case of confusion in science, but I'm a bit uncertain about it, and would like to air it to get reactions.

In high-school biology class, we are told that the highest/ most basic division among life on Earth is between 2 kingdoms: prokaryotes and eukaryotes. Eukaryotes are all those organisms whose genetic material is encapsulated within a nucleus; Prokaryotes are organisms whose genetic material is not. In other words, Prokaryote=df not-Eukaryote.

However, in the last 2-3 decades, the highest taxonomic level has slowly switched to a three-group classification: Eukaryotes, Archaebacteria, and (Eu)bacteria. Why? The short answer is: "on the molecular level, [archaebacteria] resemble other procaryotes, the eubacteria, no more (probably less) than they do the eukaryotes" (C. Woese et al., PNAS 1990 p.4577).

The upshot for present purposes is that there are actually two distinct highest taxa whose genetic material is not enclosed within a nucleus, viz. the archaebacteria and the eubacteria. From this point of view, it appears that 'prokaryote' conflates the archaebacteria and the eubacteria. But if we recall the earlier characterization of 'prokaryote' as simply 'not-eukaryote,' then 'prokaryote' does not appear to be a confused term. So the question is: Is 'prokaryote' confused, or not? (And why?) I'm happy to hear just intuitions, as well as intuitions backed up with some sort of argument or evidence.

P.s. -- For some readers, this discussion will immediately call to mind Quine's solution to the 'grue' paradox in his paper "Natural Kinds" (in Ontological Relativity and other essays). There, Quine notes that if the predicate P picks out a natural kind, then not-P usually doesn't. A hackneyed example: 'gold' picks out a natural kind (any matter with atomic number 79), but 'not-gold' does not, because it covers many, many completely disparate things -- there are too many ways to be not gold for 'not-gold' to refer to a natural kind.

This might make us think that many/ most predicates of the form not-P are, in fact, confused, since such predicates most often apply to many different natural kinds. All I can say at this point is: that sounds counterintuitive to me... it doesn't feel to me like 'not-gold' conflates distinct things.

Scott Soames' "Actually" in Vegas

One of my favorite philosophers, Scott Soames, was in Vegas last weekend; he gave a great talk entitled "Actually", and he and his wife Martha took a trip with some of the folks in my department out to the beautiful Valley of Fire state park.

One of the main points Soames pushed was that "actually" plays two very different roles in philosophical semantics. 'Actually p', spoken in a given world W1, means 'p is true in world W1' (sorry, I can't do corner-quotes in Blogger). Now, Soames says there are two ways to specify this world W1:
(1) by picking it out purely indexically, in the way 'I' picks out the speaker of the token, 'now' picks out the moment of utterance, etc. -- so on this way, 'actually p' means 'p is true in THIS world' (or '...in OUR world').

(2) by (roughly- see Soames' paper for the gory details) giving the proposition associated with the Carnapian state-description of W1. (A state-description assigns a value of true or false to every atomic sentence in a language.)

Scott pointed out that if we pick out world W1 in the second way, then 'Actually p' is a priori: once you have a state-description of the world in which that sentence is uttered, then you have all the information you need to figure out its truth-value. This runs contra the conventional wisdom that says 'Actually p' is a posteriori, since we only learn whether p is true in this world via experience; Soames's point was that 'Actually p' is learned via experience when we use way (1) of picking out the world W1, but since there is this other way (2), 'Actually p' is in fact knowABLE a priori, if not knowN a priori in practical cases.

This is very clever, and I need to think more about it, but I think my esteemed colleague James Woodbridge had the best question/ objection of the afternoon. He said 'Actually p' does not just mean 'p is true at world W1,' but rather 'p is true at W1 AND W1 is actual/ instantiated.' Someone could give me the entire state-description of the world we currently inhabit, and then I could calculate from that description that p is true in a world satisfying such a description -- but I still wouldn't know that 'Actually p' is true, because I wouldn't know that the state-description matched this world. (And I was too slow on the uptake to grasp Soames's reply to James.)

My favorite part of Soames's whole talk, though, was the following approximate quotation:
"Perhaps the contingent a priori is just an old wives' tale."
I know I can't get my grandmother to stop talking about Kripke...

Methodological naturalism without metaphysical naturalism

A student of mine pointed out to me this recent New York Times article. It's about Marcus Ross, who recently received his Ph.D. in geology, writing a perfectly normal geology dissertation about what happened 10-15 million years ago -- except this guy is actually a young earth creationist, that is, he believes the Earth is no more than 10,000 years old, based on a literal interpretation of Genesis. Ross says he works within one "paradigm" when writing his dissertation and working within the geological community, but he does not accept this paradigm for all contexts.

A number of interesting things could be said about this (and many are in the NYT article). I wanted to highlight one of the more philosophical aspects of this case. In the context of the debate over Intelligent Design, the anti-evolutionists often say 'Darwinism is a religious belief (perhaps atheism in disguise).' Many pro-evolutionists respond by drawing a distinction between methodological naturalism and metaphysical naturalism, where only the second is anything close to a religious belief. Here's a rough characterization:

(Methodological Naturalism) Scientific explanations cannot appeal to supernatural causes.

(Metaphysical Naturalism) There are no supernatural causes.

The pro-evolutionists say that science only requires methodological naturalism, not the metaphysical naturalism that is pretty close to atheism. So one could be a methodological naturalist, but need not be a metaphysical naturalist (though presumably not vice versa). One natural response the anti-evolutionist could make is that this distinction is contrived, artificial, or otherwise objectionable.

Well, now Marcus Ross is a striking real-life example of someone who is a methodological naturalist without being a metaphysical naturalist. You might think this would make the pro-evolutionists happy -- but as the NYT article makes clear, not all of them are. There are different reasons for this dissatisfaction (e.g., the young earth creationists can now claim this bona fide geologist is on their side). But one thing that perhaps drives the dissatisfaction is that, to quote the student who showed me this article, this person's beliefs seem "crazy". His mental life seems fragmented or segregated in the extreme.

Somewhat ironically, this case appears to serve as a particularly vivid example in favor of the anti-evolutionists' claim that the distinction between methodological and metaphysical naturalism is bogus. On the other hand, in defense of the distinction, perhaps it is not this geologist's metaphysical supernaturalism that makes his stance seem odd, but rather his further beliefs about the particular, specific nature of the divine causes, viz., creating the Earth 10,000 years ago or so.

A difference between science and the humanities?

This post is going to be overly ambitious and overreaching, but isn't that what the blogosphere is all about? Classes started this past week, and I am teaching an upper-level course in philosophy of science. I started the class with the (overly ambitious) question 'What is science?' We had an interesting conversation, and I learned a bit from my students. There was an extended discussion about which particular parts of forensic science really do count as science, and the question 'What is science?' really matters there, because once something is declared accepted science, then it can be admitted into evidence in a court of law.

I had one thought concerning how to distinguish science from the humanities, which I didn't share with my students, but I figured I might try to articulate here. I think it may just be a slightly different way of putting a tired old point, but here goes.

Both the sciences and the humanities seek understanding; both offer explanations of various bits of the world. At a very abstract level, though, the kind of things each tries to explain is different. Obviously, (e.g.) Hamlet is a very different kind of thing than (e.g.) thermometer readings -- I have a more 'formal' difference in mind. When an English professor gives an interpretation of Hamlet, she has (basically: see (3) in next paragraph) ALL the stuff to be explained in front of her: the text is complete, finished. To put the point in terms of evidence instead of explanation, all the data/evidence she can offer for her preferred interpretation of the text is already in. This stands in clear contrast with (most of?) the sciences: new data is constantly being gathered, and new observations need to be explained. If a similar process were occurring in the Hamlet case, a new Act of that play would be produced every week, and various interpretations were shown to be stronger or weaker as new 'data' (i.e. texts) came streaming in.

I think many parts of philosophy are more like the Hamlet case. Take ethics for example. Murder, stealing, lying, etc. are morally wrong. This is in some sense the 'received/ established text' from which the ethicist works: an ethical theory has to explain why those things are wrong. Of course, there are thought-experiments designed to probe various parts of our ethical intuitions, but (1) these often yield contentious/ equivocal results, and (2) more importantly, I only want to say philosophy is more like the Hamlet case, not that it's identical. (Plus, (3) the English professor could potentially get some new information "around the margins" (to put it metaphorically): further historical details of Shakespeare's life, earlier drafts of texts, various facts about the circumstances of production, etc. -- there is clearly a continuum here with absolutely no new data on one end and lots of new data on the other.)

Another philosophical example would be philosophy of arithmetic. We've known that 7+5=12 for some time now, and the philosopher wants to explain how and why we know it's true. We're not getting a whole lot of new 'data' about arithmetic. As a final example, consider the enterprise that falls under the heading of 'interpretation' of various special scientific theories -- an enterprise which is frequently thought of as being particularly close to science. This industry is perhaps most developed in the case of quantum mechanics, but it thrives in general relativity, statistical mechanics, population genetics, etc. as well. On my criterion, these projects (usually) fall much closer to the 'humanities' end of the spectrum: the game here is to take some standard formulation of the theory in question (e.g. of quantum mechanics) and provide an explanation of that theory. The formulation of (e.g.) quantum mechanics is, I think, like the text of Hamlet, insofar as it is taken to exhaust what needs to be explained. However, sometimes this explanation will (either by itself, or with further specification) generate new experimental predictions. When that happens (as in some cases of spontaneous-collapse interpretations of quantum mechanics), then the project becomes more scientific on the above criterion, and less like the humanities.

Perhaps the criterion I've suggested here can partly explain why many (though by no means all!) physicists express exasperation with the philosophy of physics, and consider the enterprise pointless.

philosophy on TV

This is not a substantive post, but I wanted to let people know that (1) this blog has not died (yet), and (2) I saw Aristotle quoted in a TV commercial last night. The commercial opened up with Yao Ming (a famous basketball player, for those of you who don't care about such stuff) practicing shooting 18-foot shots, making one after another. Then the screen is replaced with the text: "Excellence is not an act but a habit. --Aristotle"

I think the ad was paid for by the NBA, but I'm not sure. I'm now trying to figure out how to market my own writings to fit various basketball-related themes... I could use the royalties, but I don't see how "Tarski's theory of truth was not motivated by physicalism" or "Developmental biology may not reduce to molecular biology" could tie in with any of the, uh, virtues extolled by basketball culture.

p.s.: Does anyone know why one of Shaquille O'Neal's nicknames is "The Big Aristotle"?

Newton's God

The following three claims from the General Scholium of Newton's Principia have never made sense to me:

God "is not duration or space, but he endures and is present. He endures forever, and is everywhere present; and by existing always and everywhere, he constitutes duration and space. ... He is utterly void of all body and bodily figure."

What I cannot understand is how anything could exist always and everywhere, yet be neither body nor space nor time. Is there some further option for Newton? (Additionally, what does it mean that God 'constitutes' space and time?)

One of my students cleverly noted that Newton introduced the notion of a mutually attactive force between every two bodies in the universe; perhaps this can serve as an analogy for a Newton's God, giving me the 'further option' I'm hoping for -- since such a force is neither body nor space nor time? Unfortunately, in that same Scholium, we find an important disanalogy between the universal attractive force and God:
"In him are all things contained and moved, yet neither affects the other: God suffers nothing from the motion of bodies; bodies find no resistance from the omnipresence of God."
Presumably, any supposed force that affects nothing at all is not a force at all.

Are there any other possibilities for helping Newton out?

-----------
p.s. I found the following attempt to save Newton, from my old teacher Ted McGuire, in his "Existence, Actuality and Necessity: Newton on Space and Time," Annals of Science 1978 (how did people do research before the internets?):
"We can plausibly reconstruct the following argument. To say that God is everywhere with respect to space, is to say that one and the same individual exists at each place in extended space. To make such a claim is a contradiction only with respect to the manner in which extended things exist spatially. For they cannot as complete beings exist at once in each "part" of the place they occupy. But there is no contradiction in holding that an essentially non-extended being is capable of so existing. ... God is therefore omnipresent just in the sense that he remains numerically and unalterably the same individual at all places whatsoever. The conception appears paradoxical. However, Newton would claim that it only seems so, if we persist in imagining God's presence in space as we think of bodies individually occupying their determinate places." (p. 506)

But we can't allow ourselves the premise that Newton's God is "an essentially non-extended being," since in the General Scholium, Newton (apparently) says exactly the opposite. (Ted is right that Newton's God is incorporeal, but that isn't the same as non-extended -- think of Newton's absolute space.)