Brains

"Brains" Moves

2006-07-26T07:34:00.000-07:00

This blog has been quite successful, growing to an average of almost 100 unique visitors per day. I have decided to move it to its own domain name, using a more sophisticated blogging tool.

From now on, all new posts will appear only on the new website.

The blog is now at www.philosophyofbrains.com. Please update your links, etc.

And to entice you to visit the new website, I will post some important news as soon as I'm done with this.

News

2006-07-25T08:13:00.000-07:00

Philosophers' Carnival #33 here.

Augenblick reports on various interesting things, including the following:

The "brain box," a new computer that attempts to mimick the fault-tolerant characteristics of the brain, is being built by scientists at the University of Manchester.

The first neurons to develop in the brain have been identified by researchers at Yale University.

New Philosophical Challenge

2006-07-24T06:49:00.000-07:00

Check it out at Zeno's Coffehouse.

Some Philosophical Fun

2006-07-18T14:21:00.000-07:00

Courtesy of Ben Ricker:

"The BBC web site posted several thought experiments that are/were in vogue in ethics and requested votes on what you would do. Some food for thought. Check it out here. After you vote, you see the total tallys."

Did Fodor know about Sellars?

2006-07-18T07:11:00.000-07:00

It is sometimes noticed that Wilfrid Sellars's work in the 1950s is the origin of functional role semantics, contains the language of thought hypothesis, and has a lot in common with functionalism generally. So, it is natural to speculate the Hilary Putnam and Jerry Fodor, when they formulated functionalism in the 1960s, were influenced by Sellars. For instance, Dennett says that Putnam's functionalism was influenced by Sellars's work.

Putnam certainly knew of Sellars's "Empiricism and the Philosophy of Mind" (1956), which was heavily discussed at the time. But there is no evidence that he knew any other work by Sellars, or even that Sellars's work had a large influence on Putnam's functionalism.

As to Fodor, I know of no evidence that Fodor knew anything about Sellars's work. Fodor told me he doesn't remember knowing Sellars's work at the time.

I have discussed the evidence I could find about this in my "Functionalism, Computationalism, and Mental Contents" (in Canadian J. Phil.)

More recently, Bill Lycan told me he thought Fodor must have known of Sellars's work, because Fodor and Chihara, "Operationalism and Ordinary Language" (1965) uses Sellars to criticize Wittgenstein. Unfortunately, upon checking, I was unable to find any references to Sellars in the paper by Fodor and Chihara.

Does anyone know of more evidence bearing on whether Putnam or Fodor knew about Sellars's functionalism in the 1960s?

Kim vs. the Subset View of Higher Level Properties

2006-07-16T06:48:00.000-07:00

Jaegwon Kim is a prolific and influential writer on the topic of higher-vs.-lower level properties and mental causation. Many of his arguments may be seen as raising the following dilemma: either higher level properties reduce to lower level ones (i.e., their causal powers are identical to the causal powers of their lower level realizers), or higher level properties are epiphenomenal.

But it has always seemed to me that the "subset view" escapes Kim's dilemma. By subset view, I mean the view that higher level properties are a part of their realizers, in the sense that their causal powers are a subset of the causal powers of their realizers. (The subset view occurred to me years ago while reading Kim and listening to his talks. I believe a version of the subset view has been defended by Sydney Shoemaker, though I haven't read Shoemaker's work. I took the term from Gillett and Rives's recent paper in Nous. The subset view as I understand it seems consistent with different views of properties: either properties as individuated by their causal powers, or properties as constituted entirely by their causal powers.)

The subset view escapes Kim's dilemma because being a proper subset of something is not the same as being identical with something, and yet there is no reason why a subset of the causal powers of a realizing property (which is assumed to be causally efficacious) should be epiphenomenal.

But to the best of my knowledge, Kim has not discussed the subset view in print. I was interested his opinion, so I emailed him and asked: do you agree that the subset view is a legitimate alternative to reductionism and epiphenomenalism about properties? If not, why? If you reject the subset view, why do you?

The following is an excerpt from Kim's response (reproduced with permission):

"No, I don't think one can escape the mental causation problem by defining "realization" in the way you describe. From the start, this approach looked to me like an attempt to solve a substantive philosophical problem by definitions. Don't you think it sound too neat and too good to be true? One way to see the problem with it is this, I think: If you define a realizer in the way suggested by the "subset" view, how do you show--what does it take to show--that mental properties have physical properties as their realizers? That is, how does one show that the physical realizes the mental? The subset view looks plausible at first blush, I think, because it is presented with the unspoken assumption in the background (which we normally make under our more or less intuitive and unspecific notion of realization) that the mental is physically realized.

"Consider a mental property M. How does M get to have a physical property, P, as one of its realizers? According to the subset definition, the causal powers of M must be a subset of the causal powers of P. How is that possible? We may assume that most of P's causal powers are powers to cause other physical events but we can allow, at this point, that P's causal powers may include causal powers to cause nonphysical events as well. But for the present strategy to work for the mental causation problem, the causal powers of M must include at least some of P's physical causal powers. This amounts to the supposition that M has causal powers to cause physical events. How do we show that? Well, showing that that is possible, or showing how that is possible, is exactly the problem of mental causation. We seem to be back to square one, and very quickly, in a small circle!"

In the rest of his email, Kim also writes that from his point of view, the subset view as I define it counts as a form of reductionism, and is unlikely to satisfy die-hard nonreductive physicalists.

I agree with Kim that die-hard non-reductive physicalists will not be satisfied with the subset view as I have defined it.

But I am not a die-hard non-reductive physicalist. I am happy to say that the causal powers of higher level properties are physical. In fact, I am happy to say that all causally efficacious properties, higher and lower level, are physical (even those higher level properties, if there are any, that are not identical to (but are "parts" of) lower level properties).

I don't think the subset view is a way of defining our way around a philosophical problem. I find the subset view attractive for independent reasons: it seems to me that the subset view accomodates the existence, robustness, and other characteristics of scientific explanations and generalizations at different levels and does so better than identity-based reductionism. This could be the beginning of a long story, but I'll have to stop here for now.

Computation, Representation, and Teleology

2006-07-15T14:43:00.000-07:00

Curtis Brown, "Computation, Representation, and Teleology," presented at E-CAP 2006, June 2006.

I just found the online (long) abstract of Brown's talk. Brown defends two necessary conditions for computation: it must operate on representations (semantic condition) and it must have the function to calculate (teleological condition).

I agree with Brown that there is a teleological condition on computation, at least in the sense of the term that is useful to computer science and cognitive science, and I have argued for this in some of my papers. I'd be curious to know more about what Brown means by "having the function to calculate". Since "calculate" is usually taken to be a synonym of "compute", Brown's teleological condition sounds circular. Unfortunately, the abstract doesn't say what Brown means by "calculate".

As to the semantic condition, I have argued at length that there is no such condition--on the contrary, in my view, computation does not require representation. One way to see this is by defining computations in terms of strings of letters instead of what the letters represent (such as, e.g., numbers). Defininig computations in terms of strings may be impractical when one is doing applications, but it is theoretically insighful.

Brown responds to my view by saying that even when computation is defined in terms of strings, the inputs and outputs of the computation are still representations. The only difference is that they represent strings instead of numbers or something else. This is an original reply, but I suspect it misses my point.

Strings can be seen as concrete entities (strings of concrete physical letters, inputs and outputs of concrete computations) or as abstract mathematical entities (strings of abstract letters, inputs and outputs of abstract computations). Either way, strings may or may not be semantically interpreted, and if they are, they can represent many things (including themselves, of course).

Here is an argument that would support Brown's conclusion. Consider a concrete computation defined in terms of strings. At the very least, it represents itself, or some abstract counterpart to itself. Strings must be represented no less than numbers or anything else does.

Yes, but the point of having a mathematical theory of strings is precisely to study certain properties of the strings without any concern for what (if anything) the strings represent. And one can do the whole mathematical theory of computation purely in terms of strings rather than in terms of what the strings represent.

So, of course, when you do the theory of strings, you need to represent the strings. But when you define computations in terms of strings, you can happily ignore what the strings represent, or even whether they represent anything at all. For all you care, they can be meaningless.

But, one might reply, once you have your computations defined over strings, don't they at least represent themselves (or some abstract version of themselves)? Sure, but everything represents itself (and many other things besides, depending on how it is interpreted). This notion of representation is not going to do the job that traditional supporters of a semantic condition on computation want such a condition to do (i.e., contribute to an account of mental representation).

Caveat: I haven't listened to Brown's presentation and I haven't read his paper. All I saw was the abstract linked to above.

New Directions in DNA Computing

2006-07-15T12:55:00.000-07:00

Ehud Shapiro and Yaakov Benenson, "Bringing DNA Computers to Life: Tapping the computing power of biological molecules gives rise to tiny machines that can speak directly to living cells," Scientific American, May 2006 issue.

Jeff Dauer noticed the above article and kindly sent me the link.

Ehud Shapiro is a great guy who works on DNA computing at the Weizenbaum Institute of Science in Israel. I met him recently at an Israeli workshop on the Nature and Origin of Computation, where he presented his work.

DNA computing is computing that exploits the combinatorial properties of DNA and RNA molecules. Traditionally, the goal is to exploit the presence of illions of molecules together to generate massively parallel computations. Lately, this project seems to be losing steam.

Shapiro and his group are pioneering a new kind of DNA computing, aimed at creating a new generation of drugs that can be released within cells depending on whether certain conditions are satisfied. Very cool stuff.

Communication by Gaze Interaction

2006-07-15T07:18:00.000-07:00

Anna-Mari Rusanen told me about this story. Kati Lepisto is a Finnish former model who is now almost completely paralized. She communicates by spelling words with her eye movements, and the best reader of her eye movements (and guesser of what she is trying to say) is her mother. Some neuropsychologists are developing a communication device based on simulating her mother. As Anna-Mari notes, this is a very interesting case of cognitive modeling. Unfortunately, the book that tells the whole story is in Finnish.

The Real-life Mary

2006-07-14T10:29:00.000-07:00

Greg Frost-Arnold has two interesting posts (first, second) on Sue Barry, a real neuroscientist who recently acquired stereoscopic vision. Her story is told in the latest New Yorker.

Progress on Mind Reading by Machines

2006-07-13T12:23:00.000-07:00

Article in today's NYT.

New Blog

2006-07-13T12:15:00.000-07:00

By Brit Brogaard. It's called Lemmings (the term was coined by Weatherson: Language-Epistemology-Metaphysics-Mind-ings). Knowing Brit, I expect her blog to be good.

Difficulties for Psychosemantics

2006-07-10T14:15:00.000-07:00

When Bill Lycan visited the NEH Seminar in Mind and Metaphysics last week, he said the problem of intentionality is much harder than the problem of consciousness, because there are four terrible problems facing psychosemantics that no one even talks about:

1. Abstract concepts

2. Metaphors (according to Lycan, "nearly every thought you have is metaphorical")

3. The fact that we can use the same name for different things

4. Propositional attitudes other than belief and desire and their varying directions of fit

(The links are to handouts by Lycan on the topic.)

It's a bit of an overstatement to say that no one talks about these problems, but they certainly have not held center stage in discussions of psychosemantics.

A Dilemma for Representationalism

2006-07-08T06:17:00.000-07:00

(Strong, Reductive) Representationalism about phenomenal consciousness is, roughly, the view that the phenomenal properties of experience can be explained by a combination of representational and functional properties.

The literature is full of putative counterexamples to representationalism (e.g., examples of putatively different experiences that represent the same thing, or examples of experiences that allegedly represent nothing). These putative counterexamples are regularly met with replies that appeal to appropriate representational properties that explain the features of the example.

The relative easiness with which putative counterexamples to representationalism can be met by imagining appropriate representational properties raises the following worry: what are the criteria for attributing representational properties to an experience?

If the game of finding the representational properties of experience is too unconstrained, the theory becomes trivial. For everything can be interpreted to represent a lot of things. So it can't be enough that experiences can be interpreted as representational; there must be criteria for establishing that the proposed representational properties are the correct ones, and these criteria should be motivated independently of the various putative counterexamples to representationalism.

But as soon as we look for criteria, we can start questioning their plausibility. The first criterion that comes to my mind is what the subject of experience takes the experience to represent. But this is not going to be enough to provide the right representational properties for a representational theory of experience. At least in my case, I have lots of experiences that as far as I can tell do not represent anything. So the representationalist must claim that pace me, my experiences do represent the right stuff. How can the representationalist convincingly show that my experiences represent what she needs them to represent without trivializing her theory?

Wide Representationalism (About Qualia)

2006-07-06T15:13:00.000-07:00

Adam Pautz, "Sensory Awareness is not a Wide Physical Relation," Nous, 2006. (The link is to an extended version of the paper.)

Today, at the NEH seminar in Mind and Metaphysics, we discussed Pautz's paper, which is an attack on wide naturalistic representationalism about phenomenal consciousness. (Wide (or externalist) reductive representationalism is the following conjunction: phenomenal characters of experience are constituted (at least in part) by what they represent, and representational contents are constituted (at least in part) by natural relations between brains, their bodies, and their environments.)

Pautz constructs the following putative counterexample (I will simplify the argument a bit). Suppose two similar individuals A and B look at two exactly similar squares. Their nervous systems are slightly different, such that it is reasonable to conclude that they have slightly different experiences. But representationalism entails that the difference in A and B's experiences is a representational difference, and naturalistic externalism entails that the representational difference depends only on some type of causal/informational relation between the experience and what it represents. But the causal/informational relation between A and B's experiences are the same, hence, wide naturalistic representationalism entails the incorrect result that A and B have the same experience, hence wide naturalistic representationalism is false.

In response, one could reject either externalism or naturalism or representationalism. One could also reject realism about the represented properties (I won't take the time to explain this move). But it's not even necessary to do any of that.

(In this paper, Pautz wishes to reject the externalist part only, while retaining the representationalist part. Pautz's argument is actually a step in a longer argument for dualism.)

The weakest bit in Pautz's argument is that he suggests he is refuting wide naturalistic representationalism regardless of what psychosemantic theory it employs, but his argument relies on features possessed by a subset of psychosemantic theories, namely, causal/informational theories. So Pautz's argument at most shows that causal/informational psychosemantic theories have a problem when applied to the contents of experience.

In psychosemantics, there are three kinds of naturalistic externalist theory: (1) theories that assign contents on the basis of relations between internal states and environmental inputs (e.g., Dretske, Fodor); (2) theories that assign contents on the basis of relations between internal states and behaviors (e.g., success semantics); (3) theories that do both (e.g., Millikan, Harman). Some theories (sometimes called two-factor theories) take into account what happens within the brain in addition to the relations between internal and external stuff. If successful, Pautz's argument refutes one-factor theories of type (1), but it does not seem to do much against two-factor theories of type (1) and theories of type (2) and (3).

Pautz does mention two-factor theories, but says it's not clear how to make such theories work. (Maybe, but this has nothing to do with his main argument.) He also mentions theories of type (2) (he seems to think Millikan's theory is of type (2)) and says he doesn't think they are going to work either, but doesn't really argue for it.

Lycan has a commentary on Pautz at the online philosophy conference, in which he calls Pautz on his lack of argument against theories of type (2) and (3). In the same place, Pautz has a reply in which he argues against theories of type (2) (still seeming to think that Millikan has a theory of type (2)). He says he doesn't think these theories work as theories of the contents of phenomenal experience, because they can't deliver contents with the right degree of fine-grainedness. (Once again, this has nothing to do with his original argument in the paper.)

In other words, when pressed, Pautz resorts to arguing that psychosemantics is hard. This is true and well known, and except for one-factor theories of type (1), it's independent of Pautz's main argument.

Philosophers' Carnival # 32

2006-07-05T21:09:00.000-07:00

Here.

Swampman

2006-07-05T20:07:00.000-07:00

Swampman is a (imaginary) physical duplicate of Donald Davidson created by a freak accident by a lighning bolt hitting a swamp. Questions: do swampman's parts (e.g., the parts shaped like a heart, liver, brain, etc.) have functions? Does swampman have intentional states? Does he have qualia? These questions have been heavily discussed in the literature. (The original examples along these lines were discussed by Boorse, Stich, and others in the 1970s.)

Today Bill Lycan said that references to swampman should be eliminated from the literature and he should never be mentioned again. His reason is that intuitions diverge. Some people think the answers to the questions about swampman are obviously yesses, other people think the answers are obviously no's (at least at first; after functioning for a while, swampman will acquire functions, etc. (this is Ruth Millikan's view)). Given this divergence, asks Lycan, what's the point of insisting one way or the other?

It reminds me of something that I think Jerry Fodor wrote somewhere: "Intuition mongering strikes me as vulgar".

Alleged Counterexample to Representationalism

2006-07-05T19:44:00.000-07:00

Bernhard Nickel, "Against Intentionalism," forthcoming in Philosophical Studies.

Today, at the NEH seminar in Mind and Metaphysics, we discussed Nickel's forthcoming paper. Nickel proposes a counterexample to representationalism, i.e., the view that the phenomenal aspects of experience are represented features of what is represented by the experience.

The counterexample is a tic-tac-toe board in which all squares are blank. If you look at it, at different times it looks as though different sets of squares in the board are more "prominent" than others. In other words, you see different patterns of squares on the board (though the actual board doesn't change). Sometimes the prominent squares form a cross, sometimes an X, sometimes a T, etc. Alleged upshot: the phenomenal aspects of experience are different but what is represented is the same, hence, representationalism is false.

I'm sorry to say that no one in the seminar (15 participants, 1 TA, Heil, and Lycan) seemed very moved by this alleged counterexample. (This includes those, like me, who are skeptical of representationalism.) Lycan said he found the counterexample interesting and thought it's not obvious what the best reply is, but he also listed eight possible replies! Others offered alternative replies. A plausible one, by Ralph Kennedy, is to say that different concepts are applied to the board in the different cases (analogously to the treatment of the dot array, an example previously discussed in the literature and mentioned by Nickel).

Undoubtedly, more alleged counterexamples to representationalism will be proposed, and more replies will be given. How fruitful is this enterprise?

Teleofunctionalism Uber Alles?

2006-07-03T14:33:00.000-07:00

This week, Bill Lycan is visiting the NEH Seminar on Mind and Metaphysics. The main purpose of his visit is to discuss representationalism about qualia.

(According to representationalism, as Lycan formulates it, qualia are represented features of what is represented by a phenomenal experience (e.g., the redness of a tomato quale is the represented redness of the tomato represented by the quale). Representation does not exhaust the nature phenomenal experience, though: there is more to experience than qualia, including what it's like to have the qualia. (Unlike others, Lycan distinguishes between qualia and what it's like to have them.) Lycan's account of what it's like, and generally of non-representational aspects of experience, is functional.)

I asked Lycan what kind of functional account he appeals to for non-representational properties of experience--specifically, whether he still subscribes to the teleofunctionalism that he defended in his 1987 book (Consciousness, Cambridge, MA: MIT Press). I also asked him whether he was aware of any competitors to his teleological formulation of functionalism.

He said he is still happy with what he said on functionalism in the 1987 book, and that he wasn't aware of any other formulations of functionalism that are still on the market. He said, "I seem to have won."

Does anyone have thoughts on this? Is teleofunctionalism the only surviving formulation of functionalism? Is there anyone who defends alternative formulations these days? (What about Cummins's functional analysis; does anyone consider that the basis for an alternative formulation of functionalism?)

Upgrade (7/7): I asked Lycan what he thinks about causal formulations of functionalism (Shoemaker, etc.) and he said they shouldn't be called functionalism because they don't specify which causal relations are relevant among the many that obtain; I asked him about Cummins's functional analysis and he said it leads to anti-realism about functions (because there are so many Cummins functions and which ones we focus on depends on our perspective; this is also Eric Thomson's point in the comments), whereas a genuine functionalism requires realism.

Mind, Metaphysics, and Philosophy of Science

2006-06-29T12:00:00.000-07:00

The theme underlying the current NEH Seminar in Mind and Metaphysics is that there is a deficit of metaphysics in contemporary philosophy of mind and a deficit of ontological seriousness in contemporary metaphysics. According to John Heil, who is the seminar organizer and director, much of the talk of counterfactuals, possible worlds, supervenience, propositions, and other devices favoured by philosophers, is ungrounded. If we can get it right on some basic ontological issues, Heil maintains, many of the central problems in philosophy of mind will be automatically solved. Once the ontology is correct, the philosophy of mind will take care of itself, as it were. For more details on this, including Heil's philosophical methodology, ontology, and view of the mind, see his recent book, From An Ontological Point of View (OUP, 2003).

I was raised to think in a different way, namely, that there is a deficit of philosophy of science in both contemporary philosophy of mind and contemporary metaphysics, and that if you want to do philosophy of science well, you need to understand science well.

Interestingly, these two diagnoses are mutually consistent.

Any thoughts on this? Does philosophy of mind need an infusion of good philosophy of science, good metaphysics, neither, or both?

Kirk Takes Zombies Back

2006-06-25T08:09:00.000-07:00

Robert Kirk, Zombies and Consciousness, Oxford University Press, 2005.

Kirk is famous for inventing phenomenal zombies--creatures physically indistinguishable from us but lacking consciousness--and for using their possibility to refute physicalism. (The undelying idea goes back to Descartes.)

Kirk published his original papers on zombies in 1974. In recent years, David Chalmers has formulated a version of Kirk's zombie conceivability argument and put it at the center of debates on consciousness.

There is now a huge literature that discusses the possibility of zombies. It is only fitting that Kirk weighs in with his own book.

Kirk is now convinced that the zombie idea is incoherent. According to Kirk's new book, sombies are not possible, and hence they don't refute physicalism, after all.

The Argument for Concept Splitting from Language

2006-06-25T06:50:00.000-07:00

In our forthcoming paper, "Splitting Concepts," Sam Scott and I argue, among other things, that the notion of concept may need to be split into linguistic representations (responsible for cognition that involves language) and nonlinguistic representations (responsible for the rest of cognition). Roughly, the reason is that linguistic cognition appears to require representations with more expressive and inferential power than the rest of cognition. Another way of putting the point is, creatures that can learn and master languages are much smarter than creatures that cannot. We need an explanation for this fact, and a reasonable explanation might involve concepts of radically different kinds.

In his comments on the version of the paper that we presented at last year's SPP, Dan Ryder suggested that the argument from language at most shows that syntactic linguistic representations are special, whereas semantic representations (i.e., concepts) may be left unaffected.

In the paper, we have a multi-pronged response to this worry.

First, in so far as syntactic representations are needed to explain linguistic cognition, they belong in the theory of concepts, broadly construed. If you will, the concepts in question are concepts of syntactic categories, rather than concepts of kinds and properties in the domain of discourse. Nevertheless, they are concepts in the same sense in which other representations are concepts, and the fact that they are usually not called concepts in the literature is only a terminological point.

Second, the exact relationship between semantic and "syntactic" representations are controversial. Depending on what they are, the argument might affect semantic representations too. (E.g., perhaps there is no sharp distinction between syntactic and semantic representations.)

Finally, even if semantic and syntactic representations are sharply distinct, it remains possible (though we don't argue for it) that semantic linguistic representations are different in kind from non-linguistic ones.

In a comment to a previous post, Dan Ryder expresses skepticism about our response to his worry. He writes:

"First: surely the psychologists' and linguists' use of a different term here indicates that they think syntactic processing involves a different kind of representation, i.e. some non-conceptual kind of representation - and isn't the paper supposed to be about the scientists' notion of concepts? And second, the theory of concepts is not "the theory of the representations that explain phenomena (1) to (6)." There's no such thing as *the* representations that explain (1) to (6). (1) to (6) will involve all sorts of perceptual representations, for instance, and most scientists doubt those belong to the same kind of representation that concepts do. (Note that many think that syntactic representations are more like perceptual representations than conceptual ones.)"

Dan's comments are relevant and helpful, but they do not affect the important point underlying our argument.

With respect to the terminological point, I agree that people typically use different terms to mean different things. The question is whether the difference is relevant for present purposes. Language is used to represent the domain of discourse, and in that respect, there is a useful distinction between semantic representations (which represent objects and properties in the domain of discourse) and syntactic representations (which do not). But syntactic representations still represent: they represent properties of linguistic structures (which are still aspects of the world, by the way). So in so far as "concept" means, roughly, representation of some aspect of the world, both semantic and syntactic representations are concepts. Also, "concepts" as psychologists use the term are representations postulated to explain certain cognitive capacities. So in so far as both semantic and syntactic representations are needed to explain the same capacity, they belong in the same psychological theory. Bottom line: given the way the term "concept" is used in the literature, there is one respect (here not very important) in which syntactic representations do not count as concepts, but there are other respects (here relevant) in which they do. And by the argument from language, linguistic representations (syntactic, "semantic," or both) are different in kind from nonlinguistic ones.

With respect to Dan's second point (contrasting perceptual and conceptual representations), I am skeptical of the traditional constrast between perceptual and conceptual representations. I think all representations are "perceptual", at least in the minimal sense that they originate with the brain's processing of perceptual information. And I think all representations are "conceptual," at least in the minimal sense that they discriminate between what falls under them and what doesn't. Perhaps the perceptual-conceptual dichotomy constitutes a continuum rather than a sharp divide. (BTW, I'm taking no stance with respect to the nativism-empiricism debate.) But this way of putting things is inadequate, because it uses the ambiguous term "concept". The whole point of our paper is that there is no single notion of concept: there are many. In one sense, concepts are linguistic representations. In another sense, they are representations undelying nonlinguistic cognition. (And there may be other ways that concepts split.)

Simulation Theory

2006-06-22T12:45:00.000-07:00

Alvin Goldman, Simulating Minds: The Philosophy, Psychology, and Neuroscience of Mindreading, OUP, 2006.

How do we understand other minds? I was introduced to this problem by a psychologist, Susan Johnson. In her course of Theory of Mind, the main debate seemed to be between those who think we have an innate theory of mind and those who think we learn the theory from experience.

Later, I found out that there was another debate, between those who think we understand other minds via a theory--the theory theorists (which include most psychologists)--and those who think we understand other minds via simulating them within our own mind--the simulation theorists. At first, I thought there was little to the theory vs. simulation debate. After all, the psychologists didn't seem too concerned with it. And besides, what exactly is the difference between understanding other minds via theories and understanding them via simulations?

Then I met Robert Gordon, the founder of simulation theory, and I read a draft of Goldman's new book, in which he defends a hybrid theory-simulation theory, with emphasis on simulation. It turns out that matters are more complicated than I thought. The debate is interesting and has far reaching consequences for both psychology and philosophy of mind.

Since I don't have time to write about it myself, if you are interested in this, you'll have to read Goldman's book. Even if you don't entirely agree with him, you'll be impressed by the wide range of evidence and considerations that he musters.

Do Determinables Exist? (2)

2006-06-20T09:57:00.000-07:00

In a previous post, I expressed scepticism about a recent argument by Gillett and Rives to the effect that determinable properties don't exist: only determinate properties do. Yesterday, we discussed Gillett and Rives' paper in the NEH Summer Seminar on Mind and Metaphysics. Curiously, John Heil (who probably doesn't read my blog) expressed the same criticism that I had made in my post (though unlike me, Heil has little sympathy for Shoemaker's "subset view").

I'll take this as an opportunity to look at a reply kindly sent to me by Brad Rives:

"Thanks for your comments on the paper. I'm not sure that I understand your response to the parsimony argument. You say: "Determinables exist because the causal powers that constitute them exist; it's just that there are other relevant causal powers beyond them. Hence, there is neither double-counting of causal powers nor causal overdetermination."
I don't see how this follows. Suppose determinables are constituted by powers that are subsets of those that constitute their determinates. It's true that on this view particulars will have the powers that individuate determinable, but the point of the simplicity argument is that the determinables won't be contributing any causal powers to particulars that aren't contributed by some or other determinate. We can thus account for ALL the powers of particulars simply by attributing determinates to them, whereas this isn't true of determinables. Assuming we should only posit those properties needed to account for the causal powers of particualrs, the argument concludes that we shouldn't posit determinables. If you suppose that both determinate and determinables are instantiated, it's hard to see how there won't be overdetermination of powers. Since some of the powers that individuate a determinate also individuate the determinable, those powers will be contributed by two distinct properties, which just is overdetermination. Convinced?"

No.

The worry about overdetermination arises only if a property is something over and above the powers that it "contributes" and most importantly, the relation bewteen a determinable property and its determinates is not analogous to the part-whole relation that holds between the powers they "contribute".

If all there is to properties is powers and the powers of determinables are a subset of the powers of determinates, then there is no double counting and no overdetermination. But even if properties are something more than the powers they "contribute," there is still no overdetermination provided that determinables stand in a part-whole relation to their determinates.

Workshop on Computation

2006-06-20T09:49:00.000-07:00

The workshop on the Origins and Nature of Computation is over. It was an amazing experience: many of the best computability theorists and computer scientists, philosophers of computation, and historians of computation discussing together.

One of the presenters, Stewart Shapiro, has a new book on Vagueness in Context (OUP, 2006), which looks very interesting, especially for philosophers interested in concepts.

Another presenter, Saul Kripke, gave a provocative talk arguing that the best argument for the Church-Turing thesis is based on the idea that computation is a form of valid mathematical reasoning, plus the principle that all forms of valid mathematical reasoning can be formalised in first order logic, the completeness of first order logic, and the fact that first order logic is recursive. Something to think about.

I wish I had time to write more on the workshop but I don't. I invite everyone to look up the presenters and their published works.

True Bill Gates Story

2006-06-16T07:12:00.000-07:00

As told by Martin Davis:

A woman heading a research group on theoretical computer science at Microsoft meets Bill Gates for the first time. She says how wonderful it is for Bill Gates to head a company that supports a group--her research group--that has little chance of generating any application before a hundred years or so.

Bill Gates looks at her, looks at the man who introduced her to him, and says: "what is she talking about?"

Randomness and Computation

2006-06-12T10:54:00.000-07:00

In my Eastern APA talk last year, I argued that a genuinely random physical process should not be counted as a computation (in the interesting sense of the term). Jack Copeland disagreed.

So here in Jerusalem, I took the opportunity to ask two "great men" for their opinion. I'm happy to say that both Michael Rabin and Martin Davis appear to share my opinion. Rabin told me that a random process is not a computation because it's not repeatable, and repeatability is a feature of computation. Davis, after resisting my question for a while (on the grounds that any actual physical process is finite and hence it's not clear in which sense it would deserve to be called random), said he wouldn't call a random process a computation.

Dinner with John McCarthy

2006-06-12T10:48:00.000-07:00

Here are some things I found out last night from John McCarthy:

When he famously created Lisp (which became the standard programming language in AI), he had gotten the idea of list processing from Allen Newell and Herbert Simon at the Darmouth conference on AI in 1956.

When he "stole" the lambda notation from Alonzo Church and used it in creating Lisp (giving credit to Church, of course), he didn't know that the lambda calculus already was an universal formalism for computation, because he had bought Church's book but didn't read it all the way through. Had he known that the lambda calculus is a universal computing formalism, he might have tried to create a language based entirely on the lambda calculus, as people did 20 years later. But that, he says, would not have been as good a language as Lisp.

When he and Marvin Minsky decided to start a research project on AI at MIT, he intentionally avoided the opinion of (then influential MIT professors) Warren McCulloch and Norbert Wiener, because he thought they would have strong views on how he and Minsky should proceed and would try to influence their research.

The Origins and Nature of Computation

2006-06-12T10:38:00.000-07:00

I'm in Jerusalem at the workshop on The Origins and Nature of Computation, which started today. Many of the most prominent historians and philosophers of computation are here (e.g., Kripke, Copeland, Sieg, Shagrir, Stewart Shapiro), and so are some of the founding fathers of computer science (e.g., Martin Davis, John McCarthy, Michael Rabin) as well as many prominent computer scientists. The workshop was organized years ago, before I got my Ph.D., hence before I was in any position to be invited. But due to the Intifada, the workshop had to be postponed. I am honored and humbled to have been invited to be here.

I hope I'll have some time to post about it.

Resources for Students

2006-06-09T13:26:00.000-07:00

My trusted assistant, John Gabriel, has created a list of online resources on how to study, write papers, apply to graduate school, publish, and get a job in philosophy. Some students may find it useful. Some of the links are to previous posts on this blog, but there is much else besides. The list is also part of my permanent website.

How to Write a Philosophy Paper

Useful web tutorials on writing philosophy papers.

Guidelines on Writing a Philosophy Paper by Jim Pryor
A Brief Guide to Writing Philosophy Papers by Richard Field
Tips on Writing a Philosophy Paper by Douglas W. Portmore
Writing a Philosophy Paper by Peter Horban
How to Write a Philosophy Paper by Jeff McLaughlin

How to Study and Keep a Reading Notebook

Each person studies differently. But there are some worthwhile strategies that most successful students use.

How to Study Philosophy from Queen’s University Belfast
How to Study by William J. Rapaport
Keeping a Reading Notebook by William J. Rapaport
Questions to Consider When Making Reading Notebook Entries from Northern Illinois University

How to Use Faculty Feedback

Recommendations on using faculty to your advantage when working on a paper.

How to Improve Your Paper by Judicious Use of Faculty

How to Apply to Graduate School

Information on whether, how, and where to apply to graduate programs in philosophy.

Applying to Graduate Schools from the Philosophical Gourmet Report
Should I Apply to Graduate School? from the University of Alberta
The Overall Ranking of Graduate Programs in Philosophy in the English-Speaking World from the Philosophical Gourmet Report

How to Publish Your Work

Some tips on publishing your work in philosophy journals.

Getting Published as a Graduate Student
On Avoiding Rejection by Journals by Nancy D. Simco
An Informal Ranking of Journals that Publish in Philosophy of Mind
Philosophy Journals: Which Ones are Responsible, Which Ones Not? by Brian Leiter

How to Get a Job in Philosophy

Advice for philosophy job seekers: General information and observations on applying for philosophy jobs.

Getting a Job in Philosophy and Getting a Job in the USA from the Australian National University
On the Philosophy Job Market
More on the Philosophy Job Market
Advice for Academic Job Seekers from Leiter Reports

Referee Humor

2006-06-09T07:04:00.000-07:00

I just saw this mockery of philosophy refereeing by Chase Wrenn. Funny.

A New History of Cognitive Science

2006-06-01T12:50:00.000-07:00

Margaret Boden, Mind as Machine: A History of Cognitive Science, Oxford: Oxford University Press, due July 15, 2006.

In my opinion, Boden is one of the best philosophers of AI and cognitive science. (I say it because she is probably less recognized and cited, at least in the U.S., than she deserves.)

For some time, Boden has been working on a monumental (two volumes, 1,600 pages!) history of cognitive science, which, I'm happy to notice, is about to come out.

Boden undersands the history of cognitive science better than most. For example, she is one of the few people who has written that the classical computational theory of mind and connectionist versions of the computational theory have a joint origin in Warren McCulloch and Pitts's classic 1943 paper, and are conceptually closer than many participants in the classicism-connectionism debate seem to realize. (See Boden, M. (1991). "Horses of a Different Color?" In Philosophy and Connectionist Theory, ed. by W. Ramsey, S. P. Stich and D. E. Rumelhart. Hillsdale, LEA: 3-19. For more details on McCulloch and Pitts's theory and its historical and conceptual importance, see my recent paper in Synthese on the subject.)

The price is steep ($225), so some of you won't be able to reserve their personal copy on Amazon. But you should at least consider asking your university library to buy it. I, for one, can't wait to see it.

Another Robot

2006-06-01T10:20:00.000-07:00

A short report on a robot designed to experiment with its environment and learn "like a human infant," based on neural network technology and testing neuroscience models. (Link courtesy of my student, Adam Hartke.)

Coma in Movies

2006-05-31T06:27:00.000-07:00

Coma is a phenomenon that philosophers of mind should probably spend more time thinking about. As Reuters Health reports, a recent article in Neurology has found that most popular movies misrepresent coma, and most people don't notice.

More on Philosophy Journals

2006-05-30T11:54:00.000-07:00

A few weeks ago, I wrote a comment on which philosophy journals are considered best. Brit Brogaard has reminded me that there is a useful post with commentaries at Leiter Reports on which journals are well behaved and which aren't.

Break

2006-05-15T02:11:00.000-07:00

I'm out of town until the end of the month.

Central APA Highlights

2006-05-02T13:16:00.000-07:00

Last weekend I was at the Central APA in Chicago. Here are some events I attended that may be of interest to philosophers of mind:

Henry Jackman, in "Fodor on Concepts and Modes of Presentation," argued that Fodor's treatment of the publicity constraint on concepts is available to a certain kind of semantic holist (contrary to what Fodor implies). Roughly, Fodor argues that concepts are constituted by reference plus syntactic form. Syntactic form is not shared, but Fodor adds that concepts are nevertheless shared because their reference is public and that's enough. Jackman suggested that any holist that believes in reference as a component of content can make a similar move: although content is holistic and hence not shared, concepts are nevertheless shared because their reference is public and that's enough.

There was an invited session on "The Extended Mind and Scientific Psychology". (1) Alva Noe argued that the physical substrate of consciousness is not limited to the brain but extends into the environment. So far as I can tell, he announced he was going to argue that the alternative view, according to which the physical substrate of consciousness is limited to the brain, is unintelligible, and hence its opposite must be true. But quite aside from the implausibility of such an argument form, I didn't catch what is supposed to be unintelligible about the view that the physical substrate of consciousness is limited to the brain. (2) Robert Rupert read a nice paper entitled, "Extended Cognition as a Framework for Empirical Psychology: The Costs Outweight the Benefits," arguing that the hypothesis of extended cognition does not help, and may hinder, the science of mind. Needless to say, his commentator, Rob Wilson, disagreed.

There was an invited session on "Mechanism in the Sciences", with Bill Wimsatt, Peter Machamer, Stuard Glennan as speakers, and Stathis Psillos and Carl Craver as commentators. The notion of "mechanism" and mechanistic explanation is undergoing a resurgence of interest in the last few years, and some people--including me--think it's going to provide new insights to the philosophy of biology, technology, and mind. Make sure you read Carl Craver's book on mechanistic explanation as soon as it comes out (from Oxford U Press).

There were other things of interest but I couldn't attend them. Curiously, all the invited sessions that I found interesting appeared to have been organized by Carl Gillett.

What Is a Mind?

2006-05-02T12:57:00.000-07:00

Last Saturday, in his Central APA commentary, Rick Grush raised this question and suggested it is the most fundamental question in the philosophy of mind. He also suggested that if you don't understand this question and its importance you are missing something.

I must be slow because I don't think I understand the question.

Is it asking what is the explanation of the mental capacities and phenomena that we observe, such as perception, problem solving, and motor control? If so, the answer lies in the usual mix of theoretical and empirical investigations that scientists and many philosophers of mind are engaged in. But that is clearly not what Rick has in mind, for he argued that the question must be answered before we proceed with our science.

Is it asking what the folk means by "mind"? If so, the anwser lies either in the conceptual analysis of folk psychology (if that project makes sense) or in some empirical study of folk psychology, but it is hardly the most important question in the philosophy of mind.

Is it asking what counts as a mental phenomenon vs. what doesn't? (E.g., is conditioning properly called a mental phenomenon or not?) If so, presumably this is largely a matter of stipulation, of relatively little theoretical importance.

Is it asking what is the essence of mind (or the mark of the mental)? But why suppose that the mind has one and only one mark or essence? And more importantly, how are you supposed to find out what the essence of mind is before you begin doing science? I thought that in so far as we believe in essences these days, we believe they are discovered empirically.

I don't think any of the above corresponds exactly to what Rick was trying to ask, but I honestly don't know what else to suggest. Any thoughts on this?

Is the Brain Digital or Analog?

2006-05-02T12:32:00.000-07:00

This is an old matter of debate in neuroscience, going back to the 1940s. The question has never been properly resolved. In my opinion, the question has never even been properly formulated.

A recent study in Nature provides evidence that "in some sensory organs and invertebrate systems, neurons can also communicate in the absence of action potentials by grading their transmitter release according to the presynaptic membrane potential, which is directly determined by the barrages of synaptic activity arriving in the cell. This graded synaptic transmission was thought to be irrelevant at the vast majority of synapses in the brain, because the electrotonic distance between the presynaptic cell and its axonal terminals was considered to large." (The quote is not from the paper but from this summary.)

This result is an interesting and straightforward challenge to the classic view according to which neural impulses are all-or-none. But when the result is formulated in terms of the digital vs. analog question, it misleadingly suggests that neural signals are both digital and analog in the sense of those terms that are used in computer science and engineering.

The notions of "digital" and "analog" that are used in computer science and engineering are relatively well defined, and in my opinion they do not map onto the homonymous but vaguer notions employed in the debate about brains. So, the brain might well be both digital and analog in some loose sense, but that has relatively little to do with digital and analog computers. (For more on this, you a draft that I've written on this here.)

Acknowledgments: Thanks to Corey Maley for telling me about this study.

Online Philosophy Conference Opens

2006-04-30T17:55:00.000-07:00

The first ever Online Philosophy Conference (OPC 2006) has begun here.

There are seven papers with commentary posted for this week, to be followed by 8-9 papers per week the next three weeks.

Anyone can read the papers and post comments. It's a great opportunity, especially for students and other people who have few opportunities to attend traditional conferences.

Splitting Concepts

2006-04-22T14:36:00.000-07:00

A widespread assumption in the literature on concepts is that concepts form a unified, or singular, natural kind, as opposed to a set of different natural kinds. That is, advocates of different accounts disagree on which kind of thing constitutes concepts, but they agree that there is only one such kind of thing (with different instances for each category).

In recent years, two young philosophers, Dan Weiskopf and Edouard Machery, have completed Ph.D. dissertations questioning this assumption, independently of each other. Dan graduated from Washington University in St. Louis roughly at the time I went there for my PNP postdoc (2003). I met him and learned about his work.

In the fall 2004, I co-taught a course on concepts with Sam Scott, who at the time was the other Wash U PNP postdoc. Sam did some ground-breaking empirical work on non-referring concepts, so he knows a lot more than I did about the psychological literature on concepts.

I wanted to learn more about Dan’s work and discuss it in class, so I asked Dan for a copy of his paper in progress, which is now available on his website. Unfortunately, the paper may not have been ready at the time. At any rate, he didn’t send it to me. But during the course, Sam and I discovered Edouard’s paper, Concepts Are Not a Natural Kind, which at the time was forthcoming in Philosophy of Science (it is now published).

Since we didn’t have Dan’s paper, we decided to read and discuss Edouard’s paper instead. We were not entirely satisfied with Edouard’s argument, but we liked the conclusion—concepts split into different natural kinds—and we thought we could find better arguments. So we wrote a paper of our own.

Our paper, entitled “Splitting Concepts”, is now officially forthcoming in Philosophy of Science.

In our paper, the argument I most care about is what we call the “argument from language”. Its conclusion is that there are at least two different kinds of concept, which may be called linguistic concepts (those that explain linguistic abilities) and non-linguistic concepts (those that explain cognitive abilities we have in common with non-linguistic animals and babies). I think this conclusion may have some appealing philosophical payoff:

Many philosophers like to point out that there are dramatic cognitive differences between linguistic and non-linguistic creatures. Language seems to carry with it a lot of cognitive power. If you combine this observation with the two common assumptions that linguistic abilities are explained by concepts and that concepts are a singular natural kind, you face a dilemma. Either non-linguistic animals and babies have concepts or they don’t. If they do, you should explain why they are not as smart as we are even though they have concepts. If they don’t, you should explain why they are as smart as they are even though they have no concepts. Either way, you need a different theory of cognition for non-linguistic animals and babies as you do for linguistically competent human beings. Needless to say, philosophers have explored both options, but I’ve never been satisfied with either of them. Alternatively, you could try to downplay the cognitive differences between linguistic and non-linguistic creatures, but that doesn't sound very appealing either. Now there is a better way out: reject the assumption that concepts are a singular natural kind. Animals and babies have one kind of conceptual mental representations. Then, babies develop a new kind of conceptual representation—linguistic representations. Once linguistic representations are in place, humans are well on their way to surpassing the intelligence and inferential power of other animal species.

Of course, this is little more than a slogan at this point. Perhaps some day it will turn into a theory.

Can a Candidate with a non-English Ph.D. get a Philosophy Job in the U.S.?

2006-04-20T11:25:00.000-07:00

I occasionally receive queries on how to get a job in the U.S. Here is my best guess on the matter. Further comments and suggestions are welcome.

The U.S. probably has the largest number of academic jobs of any country in the world, or at least the largest number of desirable academic jobs. So it is natural that some scholars with foreign Ph.D.’s consider applying for American academic jobs. What are the chances that they’ll get one, at least in philosophy?

If their Ph.D. is from the U.K., Canada, or Australia, their chances are roughly the same as people with equivalent American Ph.D.’s. Otherwise, their chances are relatively few. For one thing, few people know enough about non-English Ph.D.’s to assess their value relative to American Ph.D.’s.

The philosophy job market is competitive. Search committees are naturally risk averse, and candidates with a non-English Ph.D. are risky. Here are some possible concerns: Was their training rigorous enough? Is their research good enough? Can they relate successfully to their American colleagues? Can they teach well? Can they teach in English? Can they satisfy the constantly evolving demands and sensitivities of American undergraduates?

Even so, there are things such candidates can do to improve their chances.

1. If you are willing, consider getting a (good) Ph.D. in the U.S., U.K., Canada, or Australia, even if it’s your second Ph.D.

2. Publish in English, in well respected journals or with well respected publishing houses. (Publications in foreign languages are unlikely to help you get a job in the U.S.)

3. Go to meetings that include philosophers based in English-speaking countries (preferably U.S.) and make friends.

4. Try to get invited to visit departments in English-speaking countries (preferably U.S.), teach some courses there, and get good student evaluations. If you live in the U.S., get a temporary teaching job somewhere (even at a community college) and start accumulating good student evaluations. Perhaps invite one of your local faculty friends to observe what a good job you do while you teach, so they can write about it in their letter of recommendation.

5. Get letters of recommendation from people who know the American system, preferably people who work in English-speaking institutions. Make sure they explain why you are such an outstanding (i) scholar, (ii) teacher, and (iii) colleague (fun to talk to, person with integrity, etc.). Make sure they also explain anything that might appear weak from an American perspective (e.g., your knowledge of English).

6. Distinguish between research and teaching institutions and write different cover letters for each. Research institutions are looking for people with proven publication records in English in prestigious journals, and care a bit less about how well you teach. They might be turned off if you explain in too much detail how much you love teaching. Teaching institutions are just the opposite. They’d like to hear that your mission in life is teaching, and want to see less interest in research. They might be turned off if you stress your publications too much, because they might worry that you are not really committed to teaching.

7. Your cover letter should be as brief as possible—no longer than one page. It should explain the following: who you are, what your main achievements are, and why you are qualified for the position. Address everything in the job advertisement. E.g.: if they need you to teach Nepalese Philosophy, explain why you are qualified to do that. Also, address anything about you that might appear weird. E.g.: if you are a senior candidate applying for a junior position, explain whether you are prepared to be demoted in order to get the job.

8. In the dossier, give the best evidence you have that you can teach successfully in English. (Make sure some of the people who write you letters of recommendation address that.)

9. Writing sample: the best writing sample is a paper forthcoming in the best journal (or at least, a good journal) in your field. Next best is either a paper from the last couple of years in a good journal or a new (unpublished) but polished piece. Single-authored papers are much preferable than co-authored ones.

10. For research institutions, make sure it's clear that you are productive and have projects you are working on. On your CV, list the titles of your works "in progress".

Atom by Atom Simulation of a Virus

2006-04-11T08:05:00.001-07:00

My student Ken Johnson made the following interesting comment. It is especially relevant to those philosophers who like to casually write that in principle, everything can be computationally simulated based on the laws of physics. Notice that there is no reason to expect that Moore's law will hold up for more than a few decades:

"The article linked here refers to a study at the University of Illinois at Urbana-Champaign, where researchers simulated a small virus on a large super-computer by simulating each of about a million atoms that composed the virtual virus and some surrounding virtual water. The simulation lasted about 50 nanoseconds in simulated time. (For those not metricly inclined, 1/20,000,000th of a second). If this could be scaled by about 20 orders of magnitude, then we could simulate a human atom by atom. And let's add about 10 more orders of magnitude so we can have a useful amount of time for a thought or two. If Moore's law holds up that will only be about 150 years of technology improvement -- I won't hold my breath waiting."

Will Robots Change Our Identity?

2006-04-10T08:13:00.000-07:00

Last week I had my first radio interview, thanks to a referral by Ron Munson. I was on a program (together with another guest) by Nevada Public Radio on whether robots are changing our identity and related issues, such as whether robots are likely to take over the world (as several people have predicted). I think we don't have positive reasons to think they will--at least not yet. The mp3 file is here.

My Talk at Tucson 2006

2006-04-05T11:57:00.000-07:00

I'm in Tucson, AZ, at the conference Towards a Science of Consciousness 2006.

There are a lot more people than I expected. It's about as large as an APA meeting, I would say.

I gave my talk yesterday, arguing that conceivability arguments like the zombie conceivability argument are unsound. The zombie conceivabity argument--most prominently defended by David Chalmers--says that zombies (creatures physically identical to us but with no conscious states) are conceivable, hence possible, and hence consciousness is not physical. Most physicalists, i.e. defenders of the view that consciousness is physical, argue that zombies are not possible, and there is a large debate about what it conceivable and whether conceivability entails possibility.

As I hinted before, I am unsatisfied with this debate. I think it would be dialectically more effective for physicalists to accept the possibility of zombies but question whether that possibility is accessible to our world, in the sense of accessibility standardly used in possible world semantics. In my talk, I pointed out that the zombie conceivability argument is committed to the accessibility of zombie worlds. But, I argued, assuming without argument that zombie worlds are accessible begs the question of physicalism. I also argued that the currently standard definition of physicalism is too strong, and should be relaxed to accomodate the fact that some zombie worlds are possible but inaccessible. Finally, I argued that when the issue is properly formulated, property dualism is no less vulnerable to conceivability arguments than physicalism is. Hence, this type of conceivability argument is not going to help settle the question of physicalism.

The line of thinking presented in this paper goes in a direction quite different from all the debates I've seen in the literature. So before presenting it, I honestly wondered whether I was missing something. For instance, would Chalmers be able to easily show me that I missed the point?

David Chalmers was nice enough to attend my talk, and I am grateful to him for being there. We had a lively exchange during the discussion period. Nothing that he said made me think that I had missed anything. So I'll work more on my paper this summer, while I attend the Mind and Metaphysics NEH Seminar at Wash U. Does anyone know who else is going to attend?

Robot Nurse

2006-04-05T11:52:00.000-07:00

Looking for a nurse that won't get crabby? Try this.

Why is the Hard Problem so Hard?

2006-03-27T08:37:00.000-08:00

D. Stoljar, Ignorance and Imagination: On the Epistemic Origin of the Problem of Consciousness. New York: Oxford University Press (due out in May 2006).

Why is it so hard to explain phenomenal consciousness in physical (i.e., naturalistic, scientific) terms? Why do many find it easy to imagine zombies and other putative physicalism-refuting scenarios?

Perhaps it's because our knowledge of physics is not advanced enough--we just lack the right physical theory or the right physical concepts. This answer has always seemed to me a plausible part of the correct story on consciousness (at the present state of our knowledge). It is a natural response of those acquainted with the history of science. Just as vitalists could not imagine a physical explanation of life, or Newton could not imagine a physical explanation of gravity, etc., etc., we cannot imagine a physical explanation of consciousness. It doesn't follow that there is no such explanation.

Eventually I realized that many philosophers have made similar observations. They seem to fall into two camps.

Camp 1 (e.g., the Churchlands): even though we currently lack a naturalistic explanation of consciousness, it is within reach; we just need to do the necessary science (plus, perhaps, the right amount of conceptual analysis/revision). I think this is too optimistic: we don't even seem to have a clear idea of what would constitute a successful naturalistic explanation of consciousness.

Camp 2 (e.g., Colin McGinn): we will never explain consciousness naturalistically because our minds are incapable of acquiring the right concepts. This sounds too pessimistic: why rule out future conceptual breakthrough?

The current philosophical landscape contains no one filling an intermediate position between the above two camps. But the history of science and philosophy contains many conceptual breakthroughs; by (optimistic) historical induction, we should expect more in the future. Now it appears that Daniel Stoljar has developed this line of thinking into a whole forthcoming book. It sounds promising.

The Revenge of Grandmother Cells

2006-03-26T18:01:00.000-08:00

Take a look at this.

Computer Reads Mind

2006-03-14T11:49:00.000-08:00

An interesting technological development.

Myths About Turing

2006-03-14T09:05:00.000-08:00

David Leavitt, The Man Who Knew Too Much, Norton, 2006.

Alan Turing is an iconic figure. He was one of the main founders of the mathematical theory of computability. He proved that first-order logic is undecidable. He was one of the main brains behind the allies' successful effort to break Nazi secret codes during WWII. He designed one of the earliest general-purpose, program-controlled computers. He pioneered artificial intelligence. He was persecuted by British authorities for being homosexual. And much more.

But there are also a number of myths about Turing.

Myth #1: he invented the notion of stored-program computer. Truth: Turing's universal machines are not properly called stored-program; roughly speaking, this is because they have no memory component separate from input and output devices.

Myth #2: he created the computational theory of mind, according to which mental capacities are explained by neural computations. Truth: the computational theory of mind is due to Warren McCulloch, who published it in 1943 in collaboration with Walter Pitts.

Myth #3: Turing committed suicide because of being persecuted for his homosexuality. Truth: well, myth #3 might be true, for all we know. But there is very little evidence for it. Turing might have committed suicide for other reasons, or he might have died because of an accident. Turing's archives in Cambridge contain a lot of testimonials by people who knew and saw Turing during the last weeks of his life, many of whom express doubts that he committed suicide. To my knowledge, no historian has done justice to those documents in print. At a minimum, it's fair to say that no one knows why he died.

In his new book, author David Leavitt misses a perfectly good opportunity to correct some of these myths about Alan Turing. In addition, the book contains a lot of technical mistakes. For example, Leavitt mistakenly states that Kurt Gödel showed that Bertrand Russell and Alfred North Whitehead’s system in “Principia Mathematica” was inconsistent. (what Gödel actually showed is that if the system is consistent, then it is incomplete.)

If you wish to read more serious work on Turing, you should read articles by Wilfried Sieg and Jack Copeland. References may be found in my own article on Turing, or on their websites. (However, be aware that Copeland subscribes to myth #1, and as I argue in that same article, Sieg is not always right either.)

Pitt HPS Places 10 out of 10

2006-03-13T14:11:00.000-08:00

Leiter Reports has a page up for posting junior philosophy hires.

We at University of Missouri - St. Louis hired John Brunero, a graduate of Columbia who works in ethics and political philosophy.

My alma mater, History and Philosophy of Science at the University of Pittsburgh, placed 10 candidates out of 10. 9 are in tenure-track positions and one has a post-doc at Yale. (One of the 10 is not yet listed because although he has an offer, he is waiting to hear from another place.)

Edouard Machery noted to me: "100% with 10 people. Pretty impressive, I think." I concur.

Pitt HPS has been traditionally associated with general philosophy of science and philosophy of physics, and more recently, with philosophy of biology. But others, including aspiring (science-oriented) philosophers of mind should seriously consider it. It has an excellent track record in philosophy of psychology/neuroscience. As a bonus, students have easy access to the faculty of the Pitt philosophy department.

Models in Science

2006-03-13T10:19:00.000-08:00

R. Frigg and S. Hartmann, Models in Science, Stanford Encyclopedia of Philosophy, (Spring 2006 Edition), Edward N. Zalta (ed.), forthcoming URL =
http://plato.stanford.edu/archives/spr2006/entries/models-science/>.

The Stanford Encyclopedia Entry on scientific modeling is out (since February 27, 2006). The authors are among the organizers of the upcoming conference on Models and Simulations. I expect that many philosophers of mind would benefit from reading their encyclopedia entry (and related literature).

Should Philosophy Be Experimental?

2006-03-09T10:56:00.000-08:00

Experimental philosophy is a recent philosophical movement. In spite of the name, its proponents do not attempt to do philosophy by conducting experiments. Strictly speaking, they don’t conduct experiments at all (at least in the literature I’ve read).

They conduct surveys, however, in which they ask for subjects’ opinions on a variety of philosophically relevant subjects. Examples include whether certain actions are intentional or which of two people a name refers to (e.g., assuming that the true discoverer of the incompleteness of arithmetic was not named “Gödel,” does “Gödel” now refer to the person who stole the theorem’s proof and who was named “Gödel” or to the proof’s true author?). The results of these surveys may be used as data for theories of people’s concepts and cognitive processes. They may also be used as data to test philosophical accounts of various folk notions, such as reference and intentional actions. So far, this sounds like a careful methodology for conceptual analysis (a traditional philosophical enterprise) or cognitive science (an enterprise to which philosophers traditionally participate).

Some experimental philosophers draw stronger conclusions. They reject conceptual analysis. For folk intuitions appear to be more variable and less stable than is often assumed. In other words, different people have different folk notions, or they easily change them depending on contextual factors. Hence, some experimental philosophers maintain, philosophers have little business in offering conceptual analyses of folk notions and drawing philosophical conclusions from them.

(Of course, there are philosophers who reached similar conclusions about the instability of certain intuitions without conducting rigorous surveys (e.g., Peter Unger, in his book Philosophical Relativity). But at the very least, it’s good to replace softer data with harder ones. When it comes to folk intuitions, experimental philosophers’ data are harder than most other philosophers’.)

Given all this, experimental philosophy is controversial, and for good reasons. I, for one, have heard exaggerated claims about the consequences of their work. (For instance, by my friend Edouard Machery when he gave a talk in Barcelona.)

The rejection of conceptual analysis may be taken too far. Even if folk intuitions are unstable, there is still room for analyzing concepts, provided that one is careful about what one is analyzing and what follows from it.

A perfect example of an overly strong conclusion drawn from conceptual analysis is David Chalmers’s dualism. Chalmers argues that phenomenal consciousness cannot be physical, and an important premise in his arguments is that our folk notion of consciousness cannot be analyzed in physical (or functional) terms. But at most, this argument shows a limitation of our (current) folk notion. It doesn’t show anything about consciousness itself. If folk notions turn out to be variable and unstable, it is all the more dangerous to draw strong metaphysical conclusions from their analysis.

Nevertheless, experimental philosophy does not undermine more modest analytical projects. In fact, the work of experimental philosophers may be used as a more sophisticated evidential basis for certain kinds of conceptual analyses.

Whether or not you agree with any of the above, I hope this brief discussion shows that experimental philosophy is interesting and valuable, and cannot be summarily dismissed.

But recently, experimental philosophy made it into a Slate article. You may want to forgive the journalist for not capturing every wrinkle in the philosophical debate. But the article ticked off David Velleman, who posted an unpleasant comment on Left2Right. Velleman wrote, roughly speaking, that experimental philosophy is trivial, and it’s not even philosophy. Since Velleman is a professional philosopher who should know better, you may want to be less forgiving towards him.

Of course, experimental philosophers quickly responded with a comment posted on Leiter Reports. Here are some other comments and links. In their response, experimental philosophers point out that Velleman is not well informed on their work.

In a comment on the experimental philosophers’ response, Velleman seems to suggest that experimental philosophers should find jobs outside philosophy departments. He writes: “Should departments have slots for faculty in the sub-field of experimental philosophy? Should we take time to train our graduate students in experimental design and statistics? As I said in my post, I believe that philosophy needs to inform itself about empirical matters. It's less clear to me that the relevant empirical research should itself be considered philosophy or should take up time and resources available to the discipline.”

This purism about what constitutes philosophy gives me the creeps. Does Velleman know how to draw a principled line between philosophy and other disciplines? If so, he should let us know. While we wait, I hope that other philosophers, of all people, will welcome those who disrespect so-called disciplinary boundaries.

Ironically, in his original post Velleman mentions Aristotle as someone who (unlike experimental philosophers, in his opinion) treated folk intuitions appropriately. But Aristotle spent much of his time developing empirical theories of the natural world. By Velleman’s standards, Aristotle shouldn’t seek employment in a philosophy department.

Experimental Philosophy War

2006-03-08T08:56:00.000-08:00

Since Slate published an article on so called "experimental philosophy," the debate on it has escalated in the blogosphere. Good ways into the discussion are here and here. Hopefully I'll post something on it soon.

Cognition and the Brain

2006-03-07T09:19:00.000-08:00

A. Brook and K. Akins, eds., Cognition and the Brain: The Philosophy and Neuroscience Movement, Cambridge, CUP, 2005.

A collection of articles by a group of good philosophers of neuroscience, on a wide range of topics (theory in neuroscience, representation, "visuomotor transformation," color, consciousness). Should be of interest to most philosophers of mind.

Philosophy Journals

2006-03-06T13:38:00.000-08:00

Several people asked me what the good philosophy journals are. I can't say about all areas of philosophy, but I have compiled an informal and provisional ranking based on Leiter's ranking plus commentaries that were posted on his website in the past. It contains journals that publish in philosophy of mind and related areas. Some of this information may be helpful in other areas of philosophy, but not all. (Journals that specialize in areas other than philosophy of mind are not included.)

The best guide to creating your own ranking is to look at which journals contain articles that get cited by the leaders in your field. As usual, comments are welcome.

Excellent
A) Journal of Philosophy, Philosophical Review
B) Mind, Nous, Philosophy & Phenomenological Research, Philosophy of Science, British Journal for the Philosophy of Science, Behavioral & Brain Sciences

Very Good
Philosophical Studies, Australasian Journal of Philosophy, Synthese, Philosophical Quarterly, Analysis, Biology & Philosophy, Erkenntnis, Linguistics & Philosophy

Good
Pacific Philosophical Quarterly, Canadian Journal of Philosophy, Mind & Language, American Philosophical Quarterly, European Journal of Philosophy, Ratio, Journal of Philosophical Logic, Studies in History and Philosophy of Science

OK Journals Specializing in Philosophy of Mind
Journal of Consciousness Studies, Philosophical Psychology, Minds and Machines

Update: Leiter Reports has a useful page with commentaries on which philosophy journals and well behaved and which aren't.

More on the Philosophy Job Market

2006-03-05T20:43:00.000-08:00

In a previous post, I wrote some observations on the philosophy job market. I wish to thank the many people who posted insightful comments (some of them here) and questions. A few clarifications might help. As I said before, these are rough generalizations. Every department is different, every committee is different, and every philosopher is different. Also, keep in mind that I’m only talking about junior hires.

1. It might be useful to distinguish between three types of department. First, top research-oriented departments. They are likely to consider only candidates from other top departments. They will rely on letters and pedigree, but they will also read writing samples. They won’t require publications provided that letters and writing samples are outstanding. Next, other research-oriented departments and top teaching-oriented departments. They will pay attention mostly to candidates from highly ranked programs. They will be skeptical of candidates who have not published—they’ve heard enough stories of people who seemed brilliant but never published anything. By the time they interview candidates, someone has read the writing samples, but writing samples of candidates who were not selected for an interview may or may not have been read. Finally, other teaching-oriented departments, where the majority of jobs are. They will be skeptical of candidates who look too research-oriented (based on pedigree and publications), because they fear such candidates won’t fit well in their department or will leave soon anyway. They will pay relatively little attention to writing samples.

2. It was never my intention to criticize the way departments choose candidates. Although imperfect, I think it’s a pretty efficient way of allocating resources. Perhaps some searches overemphasize pedigree. But who has the time to read 100 to 300 writing samples? And who has the skills to evaluate them reliably in their respective areas? Pedigree, after all, is not a terrible measure of academic potential, especially when suitably supplemented by other information. And besides, there are plenty of good departments that try to exploit others’ biases to snatch better candidates than they could otherwise afford.

3. If you are committed to research and your CV shows it, you may have the unpleasant experience of slipping through the cracks. You were not lucky enough to be a top choice at any research-oriented department, but your two articles in, say, Phil. Studies scared off all the teaching-oriented departments. What should you do? There is no universal recipe, but I would certainly not drop my publications from my CV. Consider whether you would be happy at a teaching-oriented department. If so, make it very clear in your cover letter next time you go on the market. Emphasize your love of teaching as much as you can. Get a temporary job at a teaching institution and point out how much you love it. Meanwhile, if you are also interested in research jobs, work hard on those paper submissions and try to get some more papers accepted at good journals. If you get enough articles in the right places, there is likely to be a research job for you some day.

4. What are the good journals? As someone pointed out in the comments, there is a ranking of journals posted by Leiter. At the time it was posted, a lot of people added comments with useful additional information, but I don’t know what happened to them.

5. By and large, I think the same considerations apply to American postdoc positions. There are few postdoc positions in philosophy, so they are usually hard to get. Having published certainly makes you more competitive.

6. Someone asked how much fellowships (Javits, Fulbright, etc.) help on the job market. If they are very competitive, they might give you a tiny boost in the eyes of some. Otherwise, they probably make no difference. These days, most job candidates have quite a list of them, so I imagine most people pay little attention.

7. Candidates who don’t have a Ph.D. from English-speaking countries (primarily U.S., U.K., Canada, or Australia), and who don’t have extensive teaching experience in any of those countries, are considered high risk and are at a huge disadvantage in the U.S. job market. If there is interest, perhaps I will post separately on their specific case.

More on the Italian Miracle

2006-03-02T13:27:00.000-08:00

In a recent post, I commented on the recent hire of a foreign candidate for a philosophy job at the University of Parma, Italy. The hire of a foreigner, without “connections,” in Italian academia is almost unheard of.

I just discovered that the search committee was chaired by Tito Magri, of the University of Roma – La Sapienza. He wrote me the following:

"I am not aware that many of my colleagues in Italy were so appreciative - although I was told that people in Parma were happy at our choice. Of course, I have no inclination to think that we set anything like a precedent."

A few comments:

1. Magri’s words are probably a nice way of saying that by hiring a foreigner without yielding to political pressures, the search committee upset many other academics, who prefer the traditional Italian way of hiring. Well done!

2. Magri doubts that other Italian search committees will follow the lead of the Parma search committee. But wouldn’t it be great if Italian philosophers started hiring based on accomplishments rather than connections?

3. Compare the influence of Australian philosophers vs. Italian philosophers. Australia has a much smaller population, and none of the academic tradition, of Italy. Yet Australian philosophers are orders of magnitude more influential than Italian ones. And consider how many brilliant minds around the world would love to live in a place as beautiful and pleasant as Italy. If Italians started hiring people from around the world based on their accomplishments, they might be able to quickly improve the quality and influence of their academic community.

4. I don’t mean to say that currently, there are no good philosophers working in Italy. Of course there are. But there is also plenty of dead weight.

5. Of course, knowing how conservative Italians are, I don’t expect much change. At any rate, don’t count on me moving there.

CFP: Models and Simulations

2006-03-02T12:35:00.000-08:00

Below is a call for papers for a conference on computer simulations. Although philosophers of mind have talked a lot about computer simulations (Turing test, anyone?), in my opinion they are very far from having reached the bottom on this important topic. I have written some of my opinions on this matter here. What follows is reproduced from the call for papers for the conference.

Two-day conference in Paris, 12-13 June 2006

www.lse.ac.uk/collections/CPNSS/events/Conferences/Simulations/

Computer simulations play a crucial role in many sciences, but they have not yet received the attention they deserve from philosophers of science. This conference attempts to systematically explore methodological issues in connection with computer simulations and the implications of these for traditional questions in the philosophy of science. Special emphasis is put on the relation between models and simulations as well as on the role of computers in the practice of science.

SUBMISSION OF PAPERS

Please send extended abstracts of 1000 words to simulations2006@yahoo.co.uk by 15 March 2006. Decisions will be made by 1 April. A few travel bursaries for graduate students are available; if you wish to be considered please submit a short (tentative) travel budget and a CV together with your paper. There will also be a Best Graduate Paper Award of 500 EUROS. For details, visit the conference website.
Deadline for submissions: 15 March 2006

Science and Common Sense

2006-02-20T06:08:00.000-08:00

Scott Sehon, Teleological Realism: Mind, Agency, and Explanation, MIT Press, 2005.

Based on this review by Sarah Worley, Sehon’s book appears to be one of the latest installments in anti-naturalist philosophy of mind.

From Kant to McDowell and beyond, there is a long tradition of philosophers who maintain that the mind as such cannot be understood by science. In alternative to science, a favorite of contemporary anti-naturalist analytic philosophers is “common sense.”

I always wonder what anti-naturalists think of the work of Freud, Skinner, Piaget, Chomsky, Miller, Newell and Simon, and thousands of other alleged scientists of the mind. Sheds no light? Haven’t gotten around to reading it yet? They rarely pronounce themselves on the matter, and when they do, in my experience they don’t exhibit a satisfactory understanding of science.

To support his case, apparently Sehon argues that common sense psychology is not proto-science. For if common sense psychology was proto-science, then it should be either reducible to scientific psychology or replaced by it, which means it cannot be an alternative to it.

I’m not sure what proto-science is. To know that, I would need to understand what science is--independently of common sense--and what a proto-X is. But as far as I can tell, science is common sense, though refined and regimented through self-conscious reflection and criticism. I don’t think this is a radical idea, or even a new one. At any rate, I think it’s better than any account of science proposed by anti-naturalist philosophers. I have defended a special version of it for the use of introspective reports in the sciences of mind (J. Consciousness Studies, 2003). Of course, if science is just refined common sense, any claim that common sense is an alternative to science is misguided.

How to Make Wise Decisions

2006-02-20T03:58:00.000-08:00

How do you choose wisely? Do you try to figure it all out at once, by consciously considering the pros and cons of every aspect of every option, or do you relax and patiently wait for the decision to pop into your head, already made by your unconscious mind? There is now scientific evidence that the former strategy leads to better decisions on simple matters, where there are few degrees of freedom, while the latter strategy leads to better decisions on complicated matters, like which house to buy or where to go to school. Hopefully, you now feel vindicated in your decision making strategies.

Dining Philosophers

2006-02-15T07:42:00.000-08:00

Did you know of the dining philosophers’ problem? It’s a classic problem in computer science, where it is used to study the sharing of scarce resources among different processes.

Five philosophers sit around the table, where they think and eat. (Isn’t that what philosophers do?) There is a fork between each philosopher, but each philosopher needs two forks to eat. Forks are picked up one at a time. The problem is to find a way for all philosophers to avoid deadlock (every philosopher has one fork but no one can eat) and consequent starvation. Starvation may also occur without deadlock if one or more philosophers never get to pick up two forks. Don’t you find it reassuring that computer scientists are busy keeping us philosophers alive and thinking?

Miracle in the Italian Philosophy Job Market

2006-02-14T07:28:00.000-08:00

I've been told that a foreign candidate has been hired for a junior philosophy job at the University of Parma. The job offer was advertised a few months ago, in English, in an international philosophy listserv. To my knowledge, this is the first time this has happened in recent years.

In Italy, there are very few academic jobs. The jobs usually go to the Italian candidates who are best connected to the local hiring committees. The candidates' accomplishments play a role, but it is a secondary role to their ability to lobby hiring committees through their academic sponsors. Ability to lobby committees is built over the years by working closely with influential Italian academics. Seniority plays a role too: the longer you've been building your connections, the more your sponsors feel obligated to lobby in your favor--regardless of whether you've been publishing in the meantime. One consequence is that to have a successful academic career in Italy, networking with local academics is far more important than publishing good work. Another consequence is that foreign candidates, or even Italian candidates who have spent long periods abroad without tending to their Italian connections, have no chance of being hired. Jobs are not even advertised in international venues.

In this case, things went differently. Marco Santambrogio, one of Italy's most distinguished Italian philosophers (he is the only philosopher working in Italy that I know of who published an article in J. Phil.), took the initiative to advertise the position, in English, in international venues. Foreign candidates applied and the hiring committee ignored the pressures coming from the sponsors of local candidates. A foreigner was hired! It looks like he was hired because of his scholarly accomplishments! (Unfortunately, I don't know his name.)

From my point of view, this is an extremely positive and welcome development. Kudos to Santambrogio and the Parma hiring committee. It remains to be seen whether others will follow their lead or whether the hire of a foreigner, based on accomplishments rather than connections, will upset Italy's philosophers to the point that they will work even harder to prevent anything like this from happening in the future.

(I have no personal axe to gind: I have never sought employment in Italian academia, and I am not planning to seek it.)

Italians and Fascism

2006-02-10T21:08:00.000-08:00

Amos Elon, “A Shrine to Mussolini,” The New York Review of Books, Vol. 53, N. 3.

Relevant personal background: I was born and raised in Italy but moved to the U.S. in 1996. Amos Elon is an Austrian Jew who immigrated to Palestine in 1933, became a major Israeli journalist and intellectual, and then moved to Italy after 1986. Independently of “A Shrine of Mussolini,” he has interesting things to say about Israel.

“A Shrine of Mussolini” is a review of the newly translated book The Body of Il Duce: Mussolini’s Corpse and the Fortunes of Italy, by Italian historian Sergio Luzzatto. The review is an excuse for Elon to investigate the baffling nostalgia some Italians feel for Mussolini: “That [Mussolini] sill finds a small number of admirers more than sixty years after his death is not easy to explain.” In fact, Elon offers no explanation.

Elon’s essay is insightful, stimulating, and mostly accurate. The main inaccuracy is revealing. Elon describes Gianfranco Fini, Italy’s current foreign minister and deputy prime minister, as someone who “announced his conversion to democracy in 1995.” This and other statements by Elon express a misunderstanding of Italian politics that is quite common among foreigners.

Fini is the leader of Alleanza Nazionale (AN). What actually happened in 1995 is that the members of the Movimento Sociale Italiano (MSI), led by Fini, dissolved MSI and founded AN instead. MSI, in turn, was the heir of Mussolini’s Fascist Party. In the face of this lineage, many non-Italians are suspicious of AN. I’ve heard Americans refer to AN as “fascists.” (Amos uses “neo-fascist” to describe MSI, though not AN.)

Fascism may be defined as “a system of government marked by centralization of authority under a dictator, stringent socioeconomic controls, suppression of the opposition through terror and censorship, and typically a policy of belligerent nationalism and racism”. None of this is advocated by AN. None of it was advocated by MSI. A partial exception is “stringent socioeconomic control,” provided that by this we mean “law and order.” But “law and order” is hardly synonymous with “fascism.”

By 1995, MSI had been a full-time participant in Italian democracy for decades. Although it was politically isolated and not welcome by other parties to participate in national governments, it participated in local administrations and had many representatives in parliament. It had no plan to overthrow Italian institutions or establish a dictatorship.

True, the founding of AN was accompanied by a new name, an emphatic public commitment to democracy, and the explicit rejection of dictatorship and racism. But this was mostly PR, intended to express values already held by members of MSI and convince (and lure) skeptics outside the party. Those MSI members who complained about the change were not proposing a return to fascism. They simply felt that the public display of good will was unnecessarily humiliating—as if they had anything to hide before.

Foreigners are not the only ones who have misconceptions about Italians and fascism. Italians have their own. There is a popular “myth of the resistance,” believed by many Italians, which goes something like this. Italians, for the most part, had nothing to do with fascism. Fascism was a movement of a few crazies who hijacked the country for a couple of decades. Since fascists imposed their rule with violence, others had little choice but to wait for a better time. Finally, during WWII, Italians took arms against fascism (and Nazism) and re-established democracy, with some help from their British and American allies. Thus the republic was born.

I, for one, came to believe something like this story when I was a kid. I probably got it from a mixture of public discourse and history textbooks.

But it turns out, as Elon correctly notes, that Mussolini was very popular during most of the twenty years he ruled the country. To be sure, Mussolini’s popularity had to do with the nationalist propaganda that he was so good at spreading. But it also had to do with the relative efficiency and stability of his government. As some Italians say, “trains arrived on time then.” Here we have a simple and straightforward explanation of the longing that a few still feel: compared with the unstable, inept, and corrupt governments that succeeded him, Mussolini seems to some Italians a strong, effective, and honest leader. But those who invoke his name—and I am certainly not one of them—are not yearning for tyranny—only for good government.

Other aspects of the myth of the resistance are incorrect. Resistance to fascism, before and during WWII, was limited to a small minority of Italians. Many of them were communists, who opposed democracy as much as they opposed Mussolini. The Italian resistance played a limited military role compared to that of the British and American armies. In 1943, with Italy partly occupied by British and American forces, the king officially fired Mussolini and Italy officially switched sides. Nevertheless, many Italians remained faithful to Mussolini and fought side by side with the Nazis. Italians repudiated fascism en masse only after Mussolini was killed in April 1945 and WWII was over. (Message to Iraqis: executing Saddam soon might help deal with the insurgency.)

People do not like to admit their mistakes. It is only natural that Italians do not like to admit they created fascism and generally supported it for twenty years. But if Italians could be more open about acknowledging their fascist past, they might see another legacy of fascism—a legacy that runs much deeper than the minute minority who still idolize Mussolini.

To control Italy, Mussolini eliminated the separation of powers. Every institution was an instrument of his rule. Besides controlling the militias, police, and army, the Fascist Party controlled the legislature, judiciary, media, schools, and professional organizations. There was even a fascist union-like organization to defend workers’ interests. Mussolini personally forged an alliance with the Catholic Church. All institutions were intertwined with the Fascist Party, and hence with each other.

After Italy returned to democracy in 1945, officially it restored a separation between executive, legislature, and judiciary. But in fact, Italy’s new leaders never created true checks and balances.

Part of the reason might have been that Italy’s democratic leaders inherited the political culture of their fascist predecessors. That was how the country worked.

Another part of the reason was a paradoxical effect of the recoil from fascism: the writers of the Italian constitution created a feeble executive with the explicit purpose of preventing a return to fascism. The president is appointed by the parliament and has virtually no power. The executive must be approved by the parliament and can be revoked by the parliament at any time. These and other clauses made the executive extremely weak, paving the way for the interminable series of short-lived administrations (average length: one year) that characterized Italy for the subsequent 50 years. It also ensured that there was little mutual control between executive and legislature, since the former had no legitimacy independent of the latter.

A related problem was the increasing strength of the Communist Party, which for decades was the second largest. Communists built an extensive political and social network, which included the largest Italian union, media, publishing houses, and many affiliated organizations reaching into every aspect of Italian society. The original aim was the communist revolution, though the Communist Party (like MSI) progressively evolved to accept democracy. In response, other parties—most notably, the Christian Democrats—created their own counter-networks, aimed at keeping Italians in the Western (and Christian) block.

When I grew up, the deep reach of political parties was felt in every Italian institution: universities, media, unions, you name it. Even judges and prosecutors were organized into “correnti,” which were groups with political affiliations. The Corte Costituzionale (the equivalent of the Supreme Court) acted as the jealous defender of the interests of the powers that be.

Here is a simple example that I am familiar with. I was in high school in the late 1980s. Each year, my high school elected four student representatives. Traditionally, two reps belonged to the local Christian student group, which was loosely affiliated with the Christian Democrats. The other two reps belonged to the local Communist student group, which was explicitly affiliated with the Communist Party. Fostering student organizations was a way for national parties to recruit voters and future leaders among high school kids. I was so annoyed by this state of affairs that in my last year, I founded an independent student group. In 1988—the year before the Berlin wall fell—I was elected along with one Christian and two Communist students. As far as I know, during my high school years I was the only student rep who was not directly or indirectly affiliated with either the Christian Democrats or the Communist Party.

Christian Democrats, who were the main ruling party between 1948 and 1994, were in an especially bad position to move away from Mussolini’s embrace of the Church. In fact, they did just the opposite. They subsidized the Church with taxpayers’ money, they hired Catholic priests to teach religion in public schools, and they let the Church influence a wide range of policies. The Church reciprocated by becoming an active propaganda machine. As a result, Italy has not enjoyed a true separation of Church and State since the days before Mussolini. Even after the fall of the Christian Democrats in the 1990s, the influence of the Church on Italian affairs has not decreased. When I left Italy in 1996, it looked like most political parties were racing to obtain the Church’s approval.

After 1989, some things began to change. The old Communist Party collapsed along with the Soviet Union, eliminating the greatest anomaly in Italian politics. The Christian Democrats collapsed under the weight of corruption investigations. Meanwhile, a grass-roots coalition proposed to reform the system for electing members of congress to make it closer to the British and American, winner-take-all system. The proposal, strongly opposed by the ruling elite, became a ballot measure that won overwhelmingly. The resulting institutional change forced Italian parties old and new to form two broad coalitions, one on the right and one on the left. This clarified the messy political scene somewhat, and helped make administrations more durable.

Still, as far as I can tell, Italy remains miles away from a liberal democracy in the sense of the term that Americans understand. Checks and balances are shaky at best. Political parties reach deep into society, especially the media. (The current prime minister owns the largest Italian private media conglomerate.) Prosecutors use the judiciary to engage in political battles. And the Church is engrained in politics.

I came to the U.S. thinking I was coming to a true liberal democracy. Since 2000, though, I’m worried that the U.S. is turning into an unwitting Italy copycat.

---
Acknowledgement: The above remarks are influenced by conversations I had in the early 1990s with Marco Pannella, an Italian leader who played a critical role in most of the positive institutional changes that occurred in Italy over the last several decades.

Graduate Student Publishing

2006-02-04T07:58:00.000-08:00

Thom Brooks, The Postgraduate’s Guide to Getting Published.

This is a very helpful guide to getting published as a graduate student. For some commentary on it, see Leiter Reports.

Students should also be cautioned not to publish too much too early. If they publish lousy work, it will haunt them for the rest of their career. Even good work is going to count in their favor only if it's published in the right places. Ideally, if a piece is good, it should be published, and it shouldn’t matter where. But things are not so simple. For readers don't have the resources to determine the quality of every article. Hence, they often decide what to read and cite based on where it is published, especially when the name of the author is otherwise unknown.

Students should be aware that where they publish is at least as important as whether they do, especially if they aspire to a job in a research institution. In my experience, search committee members pay a lot of attention to journal (and press) names. Articles in good journals are big plusses and articles in decent journals are plusses, but articles in journals that are not considered “good enough” are minuses. Students should be aware of this when deciding where to submit.

Unfortunately, the solution is not to inundate J. Phil. and Phil. Review with submissions. Most of those will be rejected, probably without an explanation. Students need to search for journals that are right for their work.

Revonsuo's Inner Presence

2006-02-02T13:53:00.000-08:00

Antti Revonsuo, Inner Presence: Consciousness as a Biological Phenomenon, MIT Press, 2006.

If you are wondering who Revonsuo is, he is a neuroscientist from Finland. I haven't read his new book but from the table of contents, it looks like a serious reflection on consciousness from a cognitive neuroscience and neurophysiology perspective. Just what we need.

On the Philosophy Job Market

2006-02-01T13:44:00.000-08:00

For the first time, this winter I observed the job market as a member of a search committee. Here are some things I wish someone had told me when I was a job candidate, or even better, when I was a beginning graduate student. Of course, they must be taken with a grain of salt: every search committee operates slightly differently.

Unless you are already in the final list of candidates for a job, your writing sample will rarely be read. Few people have the time, expertise, and confidence to judge the quality of your work on their own. Instead, they will rely on other sources of information (see below).
The rank of your institution and department counts more than you might think. Examples: “Princeton” evokes the warmest feelings because both the university and the department are good. “University of Pittsburgh” impresses philosophers because the department is good, though non-philosophers and administrators will be less moved. Even though Harvard hasn’t had one of the best philosophy departments for a while, “Harvard” is so engrained in the brains of American academics that it commands people’s attention. Conversely, if your program is not highly ranked, that counts against you regardless of whether you’ve published in J. Phil.
Virtually no one will read your published work, so they will judge it by where it’s published. J. Phil., Phil. Review, and other good journals attract people’s favorable attention. Conversely, publishing in obscure journals counts against you in any research-oriented department. Mutatis mutandis for journals in between. You should learn early on the ranking of philosophy journals and submit accordingly.
If you haven’t published anything and you still aspire to a job in a research institution, you should be from Princeton or Harvard or have extremely strong letters of recommendation from famous people.
The fame of your advisor and letter writers count for more than your might think. The bigger the name, the more meaningful the letter is assumed to be.
Letters from people outside your institution help, though not a lot.
Having more than the required three letters of recommendation helps, though not a lot.
Presenting at conferences (especially selective ones, like the APA and PSA) helps a bit more, though still not a lot.
Your cover letter doesn’t count in your favor if it’s good, but it can count against you if it’s sloppy. You should address all job requirements and say something about why you want that particular job.
The rest of your CV (honors, service, courses taken, teaching experience, etc.) counts against you if it's lacking, but does almost nothing positive for you, at least at research institutions. (E.g., no teaching experience is usually a negative.)
When you are interviewed at the APA, you are not judged on a par with the other interviewees. Search committees arrive at the APA with a more or less firmly established ranking of candidates. This ranking is based on the above considerations plus the needs of the department and the inclinations of the committee members. The best you can do in your interview, and the most likely outcome, is to confirm your place in the existing ranking. In exceptional cases, you might move upwards slightly (mostly because someone above you in the ranking did really bad). Of course, if you make a really bad impression, you will move downwards, but it's unlikely. Mostly, interviews confirm the existing ranking of candidates. So it's perfectly normal to do splendidly at your interviews but not be considered any further, simply because everyone else above you did about as well.
If you want to be competitive for jobs in teaching institutions, the rules are reversed. You shouldn’t come from a highly ranked program and you shouldn’t publish before hitting the job market. Otherwise, people will think you are too research–oriented for them. Given how many philosophers go on the job market each year, this leads to the paradox that some job candidates are not considered good enough by research institutions but are considered too good by teaching institutions. As a result, they don’t get a job. Obviously, they shouldn’t give up: they should fine tune their CV and try again next year.

Update [3/5/06]: I wrote a follow-up here.

Upcoming Conference Deadlines

2006-02-01T13:06:00.000-08:00

Some calls for papers of interest to philosophers of mind, psychology, and neuroscience:

February 15 Eastern APA

March 1 Society for Philosophy and Psychology

March 15 International Society for Research on Emotions

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2006 Computing and Philosophy conferences

European-CAP 2006 Conference
22-24 June, 2006
****February 3, 2006*** Submission of extended abstracts
Hosted by the Dragvoll campus of the Norwegian University of Science and Technology (NTNU)
Trondheim, Norway
<http://www.anvendtetikk.ntnu.no/ecap06/>

North American-CAP 2006 Conference
10-12 August, 2006
Submission deadline: ****February 28, 2006***
Hosted by the Rensselaer Polytechnic Institute (RPI)
Troy, NY
<http://www.cogsci.rpi.edu/conferences/cap/>

Asia-Pacific-CAP 2006 Conference
27-29 October, 2006
Submission deadline: ****June 30, 2006***
Hosted by The Australian National University
Canberra, Australia
<http://www.cappe.edu.au/cap2.htm>

Some General Purpose Philosophical Listservs

2006-01-21T13:37:00.000-08:00

I was recently asked which general purpose listservs in philosophy is worth subscribing to. I subscribe to the following three, which strike me as reasonably useful so far:

http://www.louisiana.edu/Academic/LiberalArts/PHIL/philosop.html
http://www.lsoft.com/scripts/wl.exe?SL1=PHILOS-L&H=LISTSERV.LIV.AC.UK
http://www.disputatio.com/esap-news/

Why the Zombie Conceivability Argument Is Unsound

2006-01-15T19:28:00.000-08:00

Perhaps the currently most popular and discussed objection to physicalism is the zombie conceivability argument, whose most famous proponent is David Chalmers. In a nutshell, the argument goes as follows: zombies are conceivable, if zombies are conceivable then zombies are possible, and if zombies are possible, then physicalism is false; therefore, physicalism is false. Replies to this argument by physicalists have focused on the first two steps: they either deny that zombies are conceivable or that conceivability entails possibility. In response to these replies, Chalmers has recently elaborated in great detail the notions of conceivability and possibility that he thinks are at stake, and argued forcefully and skillfully that in the relevant senses of conceivability and possibility, the zombie conceivability argument stands.

I am unsatisfied with the structure of this dialectic. Although I am sympathetic to both standard responses to the zombie conceivability argument, I think they are not decisive, because they are open to Chalmers’ sophisticated rebuttals. I think it might be more promising, and it would at least be useful, to scrutinize more carefully the last step in the argument. This step requires assumptions about how physicalism should be formulated as well as which possible worlds are accessible (in the sense of possible world semantics) from the actual world. It we pay careful attention to the notion of accessibility between possible worlds and formulate physicalism in a way that doesn’t beg the question, I believe we can show that even granting the first two steps of the zombie conceivability argument, the falsity of physicalism doesn’t follow. Or if zombie-philes should insist that it does, then we can construct arguments fully analogous to the zombie conceivability argument to the effect that physicalism is true.

I am going to present an exploratory version of the above at Tucson VII – Toward a Science of Consciousness 2006. My talk is on Tuesday, April 4, afternoon.

On Individuating LOT Symbols

2006-01-09T08:07:00.000-08:00

Schneider, Susan (unpublished). "The Nature of Symbols in the Language of Thought."

Schneider addresses the important problem of how to individuate LOT symbols. There is no accepted or even fully worked out solution to this problem in the literature. She gives various interesting and original arguments to the effect that LOT symbols are individuated by “total” computational role. In her view, computational role is found by Ramsifying over narrow cognitive science laws. Finally, she gives some interesting responses to the objection that if symbols are individuated holistically by their total computational role, then symbols cannot be shared. One of her responses is that cognitive science also has broad intentional laws, which do not range over symbols but over broad contents, which are publicly shared. So at least those laws apply to all subjects even though symbols aren’t shared.

Although I am sympathetic to a lot of what she says, I have some concerns.

Concern 1. Her proposal requires a non-semantic notion of symbol, but her non-semantic notion of symbol doesn’t seem to be well grounded. (Many authors have argued that nothing can be a symbol in the relevant sense without being individuated at least in part by semantic properties.) At the beginning, she appeals to Haugeland’s account of computation in terms of automatic formal systems. Unfortunately, the only clear and rigorous explication of the notion of formal systems that we possess is in terms of computation, so Haugeland’s account is circular. I think referring to Haugeland’s work in this context is unhelpful. Later, she gives her own account in terms of Ramsification over narrow cognitive science laws. But this raises the question of how these narrow cognitive science laws are to be discovered, which becomes all the more pressing in light of her stated view, later in the paper, that there are two sets of cognitive science laws: the narrow ones and the broad ones (ranging over broad contents). If ordinary cognitive science laws range over broad contents, how are we to discover the narrow ones? By doing neuroscience? (At some point, Schneider briefly mentions the “neural code,” something that in my understanding of these things, is not related to her issue.) Without at least a sketch of an account of how the narrow laws are to be found, I am unclear on how this proposal is supposed to work.

I think Concern 1 might be addressed by appealing to the non-semantic notion of computation that I have developed in some recent papers (forthcoming in Phil Studies and forthcoming in Australasian J. Phil).

Concern 2: Ramsification is popular among philosophers of mind but it is only a formal maneuver. It this view is going to have real bite as philosophy of cognitive science, Ramsification should be fleshed out in terms of some individuative strategy that actually plays a role in science.

I think Concern 2 might be addressed by appealing to functional explanation, or even better, mechanistic explanation. This is the way actual cognitive scientists go about individuating their explanantia. Schneider should be sympathetic to this move, since she appeals to functional explanation later in the paper. Notice that an appeal to mechanistic explanation is already part of my account of computational individuation, so that both Concerns 1 and 2 can be addressed by appealing to my account. The crucial observation, which is missing from her paper, is that symbols are components (or states of a component) of a computing mechanism. If you have a mechanistic explanation of a system, you thereby have access to individuation conditions for its components, including symbols (in the case of computing mechanisms).

Concern 3: Pending a resolution of Concerns 1 and 2, I would like to know more about what Schneider means by “total” computational role and especially, how it is possible to test hypotheses on whether something is a “total” computational role. If it includes all possible input conditions and internal states, it seems that total computational role can never be discovered. For how can we be sure that we have all the relevant data? Do we have to test the system under all relevant conditions? Is this even possible? Is it possible to know that we have succeeded?

I think Concern 3 might be addressed by appealing, once again, to functional explanation or better, mechanistic explanation. For as Schneider points out in various places in her own paper, mechanistic explanation gives you a way to individuate components and their activities (including, I say, symbols). Furthermore, in order to find a mechanistic explanation, you don’t need to study all possible computations. You can proceed piecemeal, component by component, operation by operation.

When you do the mechanistic explanation of a computing mechanism, you discover that total computational role supervenes on (what may be called) primitive computational role plus input and internal state conditions. So all you need to individuate a symbol is its primitive computational role, i.e. the way the symbol affects the computational architecture (components, their primitive computational operations, and their organization). So pending further explication of what Schneider means by “total”, in order to individuate the symbols, as far as I can tell you don’t need “total” computational role. (Notice that in her paper Schneider already states individuation conditions similar to the ones I suggest, under T2 and T4, but she immediately shifts from those to “total” computational role.) I think individuation in terms of primitive computational role would generate a notion of symbol that can be shared between subjects, provided that subjects share their basic computational architecture.

Did I Commit the Church-Turing Fallacy?

2006-01-05T12:36:00.000-08:00

Today I received my complimentary copy of The Philosophy of Science: An Encyclopedia, edited by Sahotra Sarkar and Jessica Pfeifer, Routledge, 2006. I wrote the entry on artificial intelligence. To my astonishment, the entry reads as follows:

If Turing’s thesis [i.e., the Church-Turing thesis] is correct, stored-program computers can perform any computation (until they run out of memory) and can reproduce mental processes (p. 27).

The italicized part is a perfect example of what Jack Copeland calls the Church-Turing fallacy, namely, the mistake of supposing that the computational theory of mind, or the view that mental processes are computational (and more specifically, that they are computable by Turing machines) follows from the Church-Turing thesis. Sadly, the Church-Turing fallacy is common among philosophers. Even more sadly, it is now firmly inserted in the entry on AI in the Routledge Encyclopedia of Philosophy of Science. Worse for me is, my name is at the bottom of that entry!

The most upsetting part of the story for me is that the offending statement was not in the original article that I submitted to the editors. The original text, which I wrote, read:

If Turing’s thesis is correct, stored-program computers can perform any computation (until they run out of memory). If McCulloch and Pitts’s theory [to the effect that mental processes are computational] is also correct, stored-program computers can reproduce mental processes.

Obviously, this is very different. Somehow, after I submitted the entry, the antecedent of my second conditional got deleted and the rest of the sentence merged with the previous sentence, turning two relatively uncontroversial statements into a fallacious one. Unfortunately, there was no proof correction, and thus no opportunity for me to notice this mistake, before publication.

I actually have a forthcoming article in Synthese criticizing arguments for the computational theory of mind that appeal to the Church-Turing thesis. Of all people, I am the last (with the possible exception of Jack Copeland) who should get caught committing the Church-Turing fallacy. Alas.

Serious Metaphysics?

2006-01-04T12:40:00.000-08:00

Bloomfield, P. (2005). "Let's Be Realistic About Serious Metaphysics." Synthese 144: 69-90.

He argues that the only sense of possibility relevant to serious metaphysics (i.e., relevant to the metaphysics of the actual world) is how things may be given how the actual world is. (This notion of possibility-given-the-way-the-actual-world-is is supposed to be related to Chalmers' secondary intensions, or Jackson's C-intensions).

Bloomfield maintains that there are no zombies at the actual world and that zombies are “actually impossible” (p. 78; this means zombies are impossible given the way the actual world is), but he doesn’t explain why he believes so.

Bloomfield says he is attacking the method or machinery employed by Chalmers and Jackson, not the way they employ it. He attacks the view that primary intensions are primary and secondary intensions are secondary, and argues that it's the other way around. But without a clear discussion of what being primary or secondary means, and what follows from it, it’s not clear what difference this makes.

Bloomfield accepts the possibility of alleged "synthetic a priori truths" but never discusses how you are supposed to discover what is possible given the way the world is. How do you discover these synthetic a priori truths, if not by the method offered by Chalmers and Jackson?

What Bloomfield really seems to dislike is the zombie conceivability argument. At bottom, his substantive point is the good old point that conceivability does not entail possibility. I agree, but it will take more than this to score points against Chalmers and Jackson’s sophisticated view.

Furthermore, conceivability arguments can be run without the distinction between primary and secondary intensions (as Kripke himself did; notice that Bloomfield occasionally cites Kripke with approval). In other words, the issue of the merits of Chalmers and Jackson’s two-dimensional semantics is largely orthogonal to the issue of the merits of conceivability arguments.

Do Determinables Exist?

2006-01-04T12:24:00.000-08:00

Gillett, C. and B. Rives (2005). "The Non-Existence of Determinables: Or, a World of Absolute Determinates as Default Hypothesis." Nous 39(3): 483-504.

They argue that there are no determinables, only determinates, on grounds of ontological parsimony. In their opinion, positing determinables on top of determinates leads to "double counting" of causal powers and consequent causal overdetermination (which are unacceptable).

They discuss both dispositional theories of properties (properties are the causal powers they contribute to entities) and categorical theories (properties are the categorical or qualitative bases for the causal powers they contribute to entities). They argue that their argument applies to both kinds of theory of property.

They discuss and reject Shoemaker's "subset" view, according to which determinables are properties constituted by a subset of the causal powers that constitute their determinates. They argue that even the subset view leads to double counting of causal powers. (Shoemaker's view is a version of a dispositional theory, but I imagine that an analogous subset view could be formulated within the framework of a categorical theory of properties.)

Unfortunately, I was not persuaded and remain inclined towards the subset view. (I'd like to remain neutral between categorical and dispositional theories if possible; I will discuss the dispositional version for simplicity.) If we maintain that determinables are constituted by a subset of the causal powers that constitute determinates, it seems to me that causal powers are only counted once, not twice. If you consider all relevant causal powers, you are considering a determinate. If you consider only some of them, you are considering a determinable. Determinables exist because the causal powers that constitute them exist; it's just that there are other relevant causal powers beyond them. Hence, there is neither double-counting of causal powers nor causal overdetermination.

Or am I missing something?

How to Improve Your Paper by a Judicious Use of Faculty

2006-01-03T15:56:00.000-08:00

During a recent conversation with Brit Brogaard, we noticed that some students may benefit from some coaching on out how to properly use faculty to their advantage when working on a paper. The rules must be adjusted for context. If you are writing a term paper, you need to work with the instructor(s) for that course; ask others to read you paper only if you have your instructor’s permission. If you are working with a thesis advisor, consult with your advisor before you send your work to others. If you are working on your own and you are at an advanced stage, feel free to ask different people for feedback. With that in mind, below are some tips that resulted from my conversation with Brit, with extra help from Taffy Ross. Mutatis mutandis, the tips apply to non-philosophy papers:

1. Before you write a paper, make an outline. State your topic and thesis as clearly as possible. An outline may be as short as a paragraph or a few bullet points.

2. Feel free to ask one faculty member for comments on your outline.

3. If you are trying to figure out which of many topics or argumentative lines to pursue, make several outlines and show them to a faculty member.

4. If you get stuck, explain your problem to a faculty member and ask for advice. You may show them an unfinished paper if that’s the only way you know to convey the problem.

5. Write an actual paper. Don’t ask faculty to comment on your notes or rambling, unstructured writing. How do you know you have a paper? At a minimum, it must begin with an introduction, state a thesis, give an argument, and offer a conclusion.

6. Treat your first draft as a final draft. Before you show your paper to anyone, edit it until you can’t stand it. Check spelling and grammar. Format the paper carefully. Check and double-check your sources and make sure you acknowledge them all. Write a complete bibliography. Make sure the quotes are accurate. Make sure your writing is clear and precise. Make sure you understand every term you use. Make sure your argument is sound (by your lights). In short, make it the best paper you can. It doesn’t have to be ready for publication, but it shouldn’t distract the reader with errors or omissions that you could have corrected by yourself. Once you’ve produced the best draft you are capable of, you may show it to one faculty.

7. While you are waiting for feedback, sit back and relax, or more likely, work on something else. Do not make any major changes until you get comments (within a reasonable amount of time). Otherwise, your reader is wasting her time commenting on something that may no longer be part of your paper. If you still have major revisions to make while waiting for feedback, it proves that you asked for feedback too early (see above).

8. If your first reader doesn’t seem to get your paper at all, stop asking her for feedback and ask someone else instead.

9. While revising your paper, do not ignore any of the comments. It is frustrating to read a second draft and discover some of the same problems, because the writer has ignored comments on the first draft. Take all comments into account. If you don’t understand a comment, ask your reader to clarify it. If you disagree with a comment, discuss it with your reader or incorporate it in the paper and give it a good response.

10. Before you ask more faculty members (besides your first reader) to comment on your paper, wait until your first reader appears to be satisfied with the paper. That is, wait until your draft receives a grade (if it’s a term paper) or comments that fail to uncover serious flaws in the paper. Only at this point should you contact other faculty members and ask them to comment on your paper. Otherwise, everyone will be spending their time identifying the same problems, or worse, giving you conflicting suggestions.

Classical Computation and Hypercomputation at the 2006 Eastern APA

2006-01-02T15:54:00.000-08:00

On Wednesday, December 28, 2006, at the Eastern APA in NYC, we held our session on classical computation and hypercomputation. (For some background, see previous posts.) From my point of view, it went roughly as follows.

In my presentation, I argued that in discussions of the Physical Church-Turing Thesis (Physical CT), we need to distinguish between what I called a bold and a modest version. According to the bold version, which is popular in physics and philosophy of physics circles, everything that can be “physically done” is computable by Turing machines. I argued that this thesis (including its more precise formulations) is both too strong (i.e., it is falsified by genuine random processes and by a liberal use of real numbers) and not related to the original notion of computation that led to work on computability theory and CT in the first place. The original notion was the epistemological notion of what problems of a certain kind can be solved in a reliable way.

To maintain contact with the epistemological notion of computation, I argued that we need to formulate a modest version of Physical CT, according to which everything that can be “physically computed” can be computed by Turing machines. By “physically computed”, I mean a process that can be used by a human observer to solve problems defined over strings of digits. In other words, modest Physical CT is true if and only if it is impossible to build a genuine hypercomputer, i.e., a device that can be used by a human observer to compute arbitrary values of a function that cannot be computed by Turing machines. Since it is presently unknown whether genuine hypercomputers can be built (though it seems unlikely that they can), the truth value of modest Physical CT remains to be determined (though the thesis is quite plausible).

Following me, Oron Shagrir discussed accelerating Turing machines, i.e., Turing machines that execute each step in half the time of the previous step. In two units of time, these (notional) machines can go through infinitely many steps, thereby performing what is known in the literature as a supertask. This feature can be exploited to compute functions that are not computable by (ordinary) Turing machines. Oron argued that strictly speaking (and contrary to what Jack Copeland had written), accelerating Turing machines do not compute functions that are not computable by ordinary Turing machines. What computes such functions is a different kind of machine, which is formed by adding to accelerating Turing machines a formal definition of how to generate the state of the machine when the machine completes the second unit of time.

Following Oron, Jack Copeland gave his comments. He said a lot of things that I agree with. I will only comment on two objections he made to my paper.

First, he argued that computability theory is about an ontic notion of computation, which may or may not occur in the physical world regardless of whether we, human observers, can access it. For example, and contrary to what I argued, even a genuine random process (if it exists) counts as a genuine hypercomputer. (Jack offered his own formulation of Physical CT, but I didn’t write it down.) Suffice it to say that I disagree. There is nothing wrong with an ontic notion of computation, which abstracts completely from issues of “epistemological embedding” (Jack’s term)—except that it’s practically useless. And computer science is about building machines to do things for us. It is this potential for use that makes computation most interesting.

Second, Jack argued that we should avoid the term “Physical Church-Turing thesis”, because what goes under that name has nothing to do with what Church and Turing were talking about. They were talking about what may be computed by human beings, and nothing more.
On this second point, Jack is in agreement with Robin Gandy, who was a student of Turing’s, and Wilfried Sieg, a distinguished historian and philosopher of computation. To support his view, Jack quoted a well known passage by Wittgenstein, according to which “Turing machines are humans who calculate”, and then proceeded to say that Turing made the same point when he said that humans who calculate are Turing machines (or something close).

Now, I do not have time to get into an extensive exegetical dispute with Jack and his allies. I have published a paper that bears on this and I hope to write more someday. But I will make a simple observation about the evidence given by Jack. First, there is no reason to believe that Wittgenstein is a reliable interpreter of Turing’s. The two disagreed on the philosophy of mathematics, as shown by their dialogue recorded in Wittgenstein’s Lectures on the Foundations of Mathematics. Second, there is a significant difference between saying that Turing machines are humans who calculate (which leaves open whether all humans who calculate, or only some, are Turing machines) and saying that humans who calculate are Turing machines (which leaves open whether all Turing machines, or only some, are humans who calculate). In other words, Turing’s statement is consistent with there being physical mechanisms that are Turing machines.

Fortunately for me, during the discussion Selmer Bringsjord, who is currently writing a paper on CT, took my side on the second point. He made the following observation. In computability theory textbooks, there are discussions of CT. Typically, these discussions do not restrict CT to what humans can compute. Instead, they assume that CT covers both humans and physical mechanisms. Are we to maintain that computer scientists and computability theorists are generally confused about their subject matter? Given Jack’s (and Gandy and Sieg’s) view, they are. Needless to say, I agree with Selmer that this is not plausible.

Why care about the Church-Turing thesis?

2005-12-25T17:08:00.000-08:00

The Church-Turing thesis (CT) says that every function that is computable in an intuitive sense is computable by an ordinary computer. Here are some reasons why you might be interested:

1. In one sense, the CT tells us the limits of physical computation: what can be computed and what cannot. For most functions cannot be computed by ordinary computers; they are usually called uncomputable functions. Is it possible to do better? Is it possible to build something computationally more powerful than what ordinary computers (like the one you are using now) can compute? This is the question addressed in my upcoming talk (see previous post). It’s a very intricate question, which has recently been subject to a lively debate.

2. Many people believe the mind-brain is a computing mechanism. If this is correct and CT is true in the relevant sense, then computers can do everything that minds can. But it’s not trivial to specify what the relevant sense is, and what the exact consequences are. If the mind-brain is not a computing mechanism, however, the Church-Turing thesis is not directly relevant to the power of minds.

3. Many people actually think that CT or some mathematical result related to it entails that the mind is a computing mechanism. In an important recent paper (published in J. Phil 2000, click here for an abstract), Jack Copeland argues conclusively that this is a fallacy. More sophisticated people have used CT in arguments that the mind-brain is a computing mechanism, but this is still a mistake. I have written a paper (forthcoming in Synthese) that shows in some detail where those arguments go wrong.

The Physical Church-Turing Thesis: Modest of Bold?

2005-12-25T16:58:00.000-08:00

This is the title of my talk at the Eastern APA, in the session on Classical Computation and Hypercomputation (see previous post). The other presenter is Oron Shagrir and the commentator is Jack Copeland. Jack is probably the most distinguished philosopher of AI and computation, and Oron is one of the best philosophers in this area. Both are probably less well known in the US than they deserve. They are, respectively, from Israel and New Zealand. If you are based in the US, you may not have many other opportunities to see them in action. So if you are in NYC next week, you should consider coming to our session on Wednesday.

Eastern APA: Classical Computation and Hypercomputation

2005-12-25T16:35:00.000-08:00

There will be a session on hypercomputation and related matters (such as the Church-Turing thesis) at the meeting of the American Philosophical Association, Eastern Division, in NYC, on Wednesday, December 28, between 5:15 and 7:15. As far as I know, it’s the first APA session entirely devoted to recent discussions of hypercomputation and the Church-Turing thesis.