Any Polish Speakers Out There?

Polish magazine Charaktery reports on my Philosophy of Flirting paper in Polish.

Although I don't speak a word of Polish, thanks to online translation site Poltran, I can reveal that what it says is:

Carrie Jenkins, On department of australian philosophy of national university in canberra doktorantka, there is author of publication titled „ philosophy flirt ”, soon it has appear in london which (who) „ ” The Philosophers Magazine. Idea of writing of article has emerged for (after) it, as it has met on way of other student of philosophy Jenkins, daniel name Nolan and it has fallen in love in it.

If anyone out there speaks Polish and can offer a more, erm, natural-sounding translation, and more generally tell us what kind of magazine this is, please write in!

In other news, the Brisbane studio where we recorded our ABC interview yesterday is today closing down!

ABC Radio National Debate

Daniel and I are confirmed to appear on ABC radio's 'Life Matters' programme on Thursday (21st December). Our interview will be aired shortly after 9.00am in Australia, and will also be available for download from the 'Life Matters' website for a couple of weeks.

Update: You can now hear the interview here. (Our piece starts about 12 minutes into the programme. At the moment you can only listen online but for the truly dedicated it will be available for download soon!)

Two Links

Ralph Wedgwood has a fun case - an 'Epistemic Newcomb Problem' - over at Certain Doubts.

Also well worth checking out: the online manuscript of Tim Williamson's new book 'The Philosophy of Philosophy'. (Hat tip: Dave Chalmers.)

Commitment and Degrees of Belief

I've recently got interested in degrees of belief. (Hang around Canberra long enough and it's bound to happen.) I've been particularly enjoying a paper by Lina Eriksson and Al Hajek called 'What Are Degrees of Belief' (forthcoming in a Studia Logica special issue on formal epistemology, edited by Branden Fitelson, to appear 2007). I won't go into the details of their paper here since it is not publicly available yet. But here's something a bit different that I started thinking about after reading their paper and chatting to Al about it.

(Caveat: I don't know much about the literature on this topic, so I'm making no claims to originality.)

It would be nice to have a unified way of explicating the notions of belief and degree of belief. My hunch is that the notion of commitment - which clearly has both on/off and gradable aspects - can help. Belief could be explicated as commitment in the on/off sense, degrees of belief as degrees of commitment in the gradable sense.

The tricky bit is going to be specifying the right notion of commitment. Here are some of the things it's not:
- the kind of commitment you take on by making a promise
- the kind of commitment you have to a proposition p in virtue of believing something which entails p (thanks to Al for this one)
- the kind of commitment you can have to a cause or a person.

Here are some things that might help pin down the right notion:
- it's a propositional attitude
- we aim to have this kind of commitment in the on/off way to a proposition p only if p is true.

Incidentally, some readers of this blog may be interested to know (if they don't already) that Studia Logica is currently calling for papers on vagueness. (I just spotted this while finding the link for the above reference.)

Life Matters

Daniel and I might be appearing on ABC National Radio on 21st December on a programme called 'Life Matters'. Discussing what, I hear you ask? The semantics of conditionals? The a priori and the Canberra Plan? Methodology and epistemology?

Amazingly, it's none of these they're interested in; it's the philosophy of flirting. Watch this space for confirmation ...

Book News

Some good news: my book Grounding Concepts will be appearing with Oxford University Press. The central aim of the book is to develop the idea of concept grounding as the basis of a new kind of epistemology for arithmetic (see my paper Knowledge of Arithmetic for a sketch). It also tries to show how some of my ideas about realism and knowledge are supposed to fit into a coherent whole together with the concept grounding story.

Now I just have to get down to writing up the final version. Any volunteers to read and criticize draft chapters would be welcome ...

(PS: Sorry about the delay with the BK workshop photos. I'm having some technical difficulties with my camera.)

AAP(NZ)

Pictures from the Basic Knowledge workshop will be appearing here soon ... I am currently away at the New Zealand AAP.

Ed Mares gave the opening presidential address on Sunday, arguing that validity was to be identified with information-preservation and not with truth-preservation. Since information-preservation was so defined as to yield the rules of a relevant logic, this allowed Ed to maintain that the connectives have meanings given by their classical truth-conditions without thereby committing himself to classical logic.
Amongst other interesting stuff, Ed argued (by way of arguing that we do not need Looney Tune, or 'that's all', facts) that whether a model is complete or partial is not a matter of whether the model contains a 'that's all' fact but a matter of our attitude to that model (i.e. whether we regard it as complete or partial). I think it would be preferable, to avoid raising realist eyebrows, to say simply that it is a fact about the model rather than a fact within the model, and leave us out of it.

New (Final?) Draft of My Boghossian Paper ...

... is now online.

More Photos

I've just posted some more photos from the grad conference.

Priest On The Logic Of Relativism

Today at the Arché grad conference Graham Priest entertained us with a fun talk on the logic of relativism.

Amoung other things, Graham considered the following problem that (some) relativists seem to face. Suppose you are the kind of relativist who thinks that as a relativist you should not make absolute claims (A), but only claims about what holds according to some perspective (SA - where S stands for 'syat', a Sanskrit term of art which apparently is used by Jains to mean something like 'from some perspective'). This gives rise to a regress: one should not assert SA absolutely but only the qualified SSA; not SSA but SSSA; and so on. It turns out nothing is assertible.

Graham proposed a system in which A and SA (and hence SSA, SSSA etc.) are all logically equivalent, and suggested that this would solve the problem, since whenever one asserts A one is thereby asserting (something equivalent to) SA, SSA and so on.

But I wondered how this proposed solution would work. The thought motivating the problem was not that the relativist should say SA as well as A, but that the relativist should say SA instead of A: that she was wrong to assert the unqualified A. If A and SA, SSA etc. turn out to be equivalent, the wrongness of asserting the unqualified A has not (for all that's been said so far) been removed. So for all that's been said so far, none of SA, SSA etc. are assertible because they are all equivalent to the unacceptable unqualified A.

Grad Conference Photos

Here are some of my photos from the Arché grad conference. More will follow ...

Tip

Look out for more coverage of next weekend's Basic Knowledge workshop over at Plurality of Words. "Extensive blogging" of the event is "promised"! (Can't get out of it now, Andreas!)

Stanley on Shared Content

Neglecting Hegel on the a priori yet again, Jason Stanley gave an exciting talk about contextual sensitivity and shared content yesterday.

The (alleged) problem of shared content for those who believe in rampant contextual sensitivity is that is that to the extent that the proposition expressed varies with context, it is harder to explain why people find it so easy to communicate (i.e. grasp what propositions others are expressing) .

Richard Heck has suggested that grasping the exact proposition expressed is not important - you just have to grasp one that is similar enough.

Jason proposed instead that one should respond by saying that it is not so hard as you might think to grasp the exact same proposition that one's interlocutor expresses. Adpoting a Russellian view of propositions enabled him to argue (if I got him right) that my grasping the exact proposition you express requires only a kind of de re understanding. It only requires that I know, de re of the things you were talking about and properties you ascribed, that you said that those things have those properties. Since the Russellian proposition expresed is just a construct out of those things and properties, not a Fregean sense, mode of presentation doesn't matter: it doesn't matter what descriptions of these objects and properties I have available, nor whether I can distinguish them from close relatives, as long as I end up with the appropriate piece of de re knowledge about them.

One question this raised in my mind is whether this move really addresses the spirit (as opposed to the letter) of the shared content problem. If we go Russellian about propositions, then arguably grasping the proposition expressed is not all that's important for communication. Modes of presentation ought to matter too.

Addendum: Thanks to Jason for correcting my spelling of 'Russellian'. I should have mentioned that the term 'problem of shared content' is due to Herman Cappelen.

Arche Trip

I'm back at Arché for a couple of weeks, where I'll be attending the Arché graduate conference and organizing the Basic Knowledge Workshop. I will be posting some event reports here as I go along.

Tonight I'm off to see Jason Stanley open the grad conference. The title is TBA, so it remains to be seen whether he will address the important yet neglected topic of Hegel on the a priori, as requested by Paula and me.

Nolan Flirts With Fame

The Aussie press has now picked up Daniel's response to my paper The Philosophy of Flirting - see the fourth item down on this page of The Australian.

The reporter offers some sage advice inspired by the work of Nolan: "If you want to flirt, send text messages, not testicles."

PGR and Other News

The long-awaited Philosophical Gourmet Report is now up. I note with interest that the ANU is ranked 15th in the world, along with my alma mater Cambridge. Nottingham comes in at joint 51st in the world.

In other news, I'm very pleased to have been offered Associate Fellowship of two research centres in the last week: the Centre for Metaphysics and Mind in Leeds and my old haunt Arché in St Andrews. Both are places where there's lots of good philosophy going on, so this is really exciting (and it raises my number of institutional affiliations to four for the rest of this academic year)!

Davies Paper

A draft of another of the papers for the Arché Basic Knowledge Workshop is online: 'Two Purposes of Arguing and Two Epistemic Projects' by Martin Davies.

Boghossian on Epistemic Analyticity

I'm posting the nearly-final draft of my paper on Boghossian on Epistemic Analyticity. Comments welcome. The paper upholds the objection that knowledge of meaning through implicit definition cannot be a source of a priori knowledge, since in order to use implicit definitions, one must already know the propositions knowledge of which we are trying to account for. This claim itself is not new, but I aim to do four new things: firstly, drawing on some recent work by my former colleague Philip Ebert, I put a new structure on the objection, showing how it works on either of two possible readings of one of Boghossian's premises. Secondly, I argue that Boghossian's recent attempts to answer this sort of objection are unsuccessful. Thirdly, I offer some new side-objections to Boghossian. Finally, I resist Ebert's reasons for thinking what's wrong with Boghossian's argument is that it fails to transmit warrant (and also explain how the objection I defend is different).

Update: The link now points to a new draft, changes to which have been based in part on the discussion in the comments on this post.

Merely Verbal Disputes

I'm planning to join the metaphilosophical fray over what counts as a merely verbal dispute. My first thought is that what counts as a merely verbal dispute is likely to depend to a fair extent on what the parties to the dispute are interested in. One obvious way it looks like this can happen is that various prima facie substantive-sounding disputes can turn out to be merely terminological if the parties are self-consciously interested in settling a point of terminology. But this isn't the only way.

For instance, consider disputants A (an externalist) and B (an internalist), who argue as follows:
A: "We both know that there is an external world."
B: "No-one knows that there is an external world."

Suppose A and B agree that they each stand in relation E to the proposition There exists an external world, where E is the relation that A, being an externalist, takes to be sufficient for knowledge. And they also agree that nobody stands in relation I to that proposition, where I is the relation that B, being an internalist, takes to be necessary for knowledge.
Now suppose that when they realize they agree in these ways, they find that this enables them to resolve all the points they were interested in. Then we might be tempted to say that their original dispute was merely a verbal dispute about 'knows'. But in fact things aren't quite that simple - we want to allow that two people could resolve a substantive dispute about knowledge by thinking about the E and I facts, even where the original dispute was a substantive dispute about the knowledge facts (as opposed to the E and I facts) and not merely a verbal dispute about 'knows'. For instance, it could be that thinking about the E and I facts helps one of them to notice the facts about the knowledge relevant for resolving their dispute. Instead, I think that being resolvable in this way is a symptom of a merely verbal dispute. It is a symptom because it (fallibly) indicates that they never really diagreed about anything they were interested in, which I think is crucial for whether their dispute was merely verbal. (That's not supposed to be a criterion by itself either, but it's closer.)

But if noticing these points of agreement does not resolve their dispute (and the same goes for any other agreements of a similar kind that they may have), then it's tempting to say their dispute is not merely verbal but concerns a substantive point about knowledge. And that's going to be because this is evidence that what they're interested in is the facts about knowledge, and not just the E and I facts (or whatever).

In fact, however, there's something appealing about the thought that their dispute might still be merely verbal even if they are interested in knowledge for its own sake. For if there are no knowledge facts as distinct from the facts about E and I, then there is nothing substantive for their dispute to be about. So their dispute - if it is to have any point at all - must boil down to a disgreement about whether 'knowledge' tracks (and/or should track) E or I. If this is right, the interests of the disputants don't always settle whether the dispute is merely verbal. Still, they surely have an impact in many cases.

Pritchard's Basic Knowledge Workshop Paper

A draft of Duncan's paper for the Arche Basic Knowledge Workshop, 'Knowledge and Value', is now available. I'm looking forward to getting a chance to read it this weekend ...

A Priori Paper

I'm posting a draft of my new paper on the a priori. Comments very welcome, as always.

(Actually p) iff p

Here's an interesting schema from the point of view of thinking about the relationship between conceptual truth and necessary truth:

A: (Acutally p) iff p

For true but contingent propositions p, this is possibly false: worlds where not-p are still worlds where actually p. Do people reckon it's conceivable that A is false for such p?

Even if it *is* conceivably false, you might think it's the sort of thing you can tell is true just by thinking about the concepts it involves. This might lead you to suspect there are two grades of conceptual truth:

1. Things you can tell are true just by thinking about the concepts involved,
2. Things such that it is not conceivable that they are false.

The second grade looks strictly stronger. (Although I'd be interested to hear if people think they have counterexamples to this claim.)

(Thanks to Daniel for making me think about this!)

More Fame

Since my last post I have been interviewed on ABC Radio! (Although before anyone gets too excited, I should mention that it was ABC Radio Hobart). I'm about to be interviewed again by RTR fm in Perth. It seems the Aussies are interested in flirting.

What I want to know is why nobody takes this kind of interest in my *fascintating* papers on the a priori. :)

Fame At Last?

I had my first philosophy-related media interview last week, with a journalist from The Australian. (This is an Australian national newspaper - in fact, as I was surprised to learn, the only Australian national newspaper.) Thanks to my post on TAR, the guy had taken an interest in my work on flirting. If anything is printed, it will be in the Higher Education supplement, which appears on Wednesdays. There may even be a compromising photo ... :)

Addendum: Here is the article.

Flirting Again

My paper on the philosophy of flirting will be coming out in The Philosophers' Magazine, so this is to say thanks to all the people who sent me comments after I posted a draft here. Unfortunately TPM won't let me include any acknowledgements in the actual article, but be assured that I am grateful for all the comments it received! Here is the probably-final version.

What Is A Necessary Condition?

Necessary conditionhood is a notion I employ all over the place, and I've only just noticed that I'm not really sure what it amounts to.

Suppose P is a necessary condition for Q. Here are some of the things I've probably taken that to mean on various occasions:

1. Q materially implies P
2. Q strictly implies P
3. ~P materially implies ~Q
4. ~P strictly implies ~Q
5. If Q then P
6. If ~P then ~Q
7. Necessarily, if Q then P
8. Necessarily, if ~P then ~Q
9. If Q were the case then P would be the case
10. If ~P were the case then ~Q would be the case

On other occasions I've taken necessary conditionhood to involve some more substantial kind of dependence, so that if P is a necessary condition for Q, then Q's obtaining depends causally, explanatorily, or in some other interesting way, on P's obtaining. So for instance another thing I've taken it to mean is:

11. If ~P were the case then ~Q would be the case *because* of ~P

All this goes for sufficient conditions too, mutatis mutandis.

Some questions this raises: is one of these understandings right and the others wrong? Or do we in fact have a wide range of notions of necessary conditionhood? If the latter, is that a good state of affairs? Should we take more care to spell out what we mean each time we use the phrase 'necessary condition'?

Opacity and Anti-Realism

Something I probably should have thought about before, but in fact only noticed in conversation with Daniel Stoljar on Friday, is that (by my lights) '... is an anti-realist about ...' can create opaque contexts, on at least some uses. I reckon that one way to to be an anti-realist about ethics is to say that the ethical facts are identical with certain facts about what we approve and disapprove of. But anti-realists about ethics needn't (even by their own lights - i.e. even given that their identity claim is right) be anti-realists about approval.

In Australia

Greetings from the ANU! Pending recovery from jetlag, I've been enjoying meeting the philosophers and other local wildlife, and listening to an interesting talk by Hilary Greaves on how in the multiverse we should rationally update our beliefs.

Epistemic Norms Paper

Things will be quieter here for a while during the run-up to my move to Canberra at the end of August.

In the meantime, here is the current rough draft of my paper on Epistemic Normativity. Comments very welcome, although I can't promise to reply quickly at the moment :(

Worlds and Women

I'm currently enjoying a paper from 1993 by Tony Roy called Worlds and Modality (the link is through JSTOR). I like his attempt to ground modal facts in actual-world structural facts about properties (see esp. section 2). Or at least, I think it sits very nicely with the kind of epistemology of modality that I'm working on defending.

In other news, Brit has an interesting post on women in Philosophy. (I'd be even more interested to know the statistics for women Lemmings ...)

Positions On The A Priori

I'm currently working on a paper on a priori knowledge, and I thought it might be helpful to start out with an overview of available positions, characterized in terms of the answers their defenders would give to a set of questions. I'd be really interested to hear whether people think anything important is missing from my overview, whether the description is helpful, etc..

Before I start, it's useful to have an umbrella term for all forms of the view that some appeal to conceptual truth or something in that area is what does (most of) the interesting epistemological work in helping us understand (at least some of ) our a priori knowledge. I'll refer to all such views as versions of the conceptual approach.

First, then, there is the question of whether or not a priori knowledge is a distinctive epistemological phenomenon at all. Those who deny this include Mill and Quine, both of whom argue, in their different ways, that what appear to be cases of a priori knowledge are in fact cases of ordinary empirical knowledge.

If it is agreed that a priori knowledge is a distinctive phenomenon, there is the question of whether or not to adopt any version of the conceptual approach. If the answer is no, then we can ask whether or not any form of factualism is correct for claims of a priori knowledge or justification: that is, whether there are facts corresponding to acceptable claims of this kind, or whether the acceptability of such claims has some other basis. Field defends a form of non-factualism, at least for basic a priori knowledge, arguing that claims of justification for basic a priori principles are merely expressions of pro-attitude towards these principles. Factualist positions available to non-defenders of the conceptual approach include innatism, certain forms of conventionalism which are not wedded to the conceptual approach, and some forms of rationalism (for instance, some of the thoughts of Gödel could be developed in this way: we could posit a priori knowledge of set theory, for instance, via a rational faculty which is 'something like a perception' of its objects, without our account appealing to conceptual truth).

For those who favour the conceptual approach, we now ask whether or not mind-independence realism is true for any of the a priori knowable subject matters that are covered by the account. Those who answer 'no' here I take to include Ayer, Carnap, Kant, defenders of implicit definition views such as Wright and Hale, and perhaps Boghossian.

Those who do want to be realists then have to decide whether to be rationalists: that is, whether to accept that some propositions can be known solely through the exercise of faculties other than the senses. (I take empiricism to be the denial of rationalism). Those who answer 'yes' to this question I take to include BonJour, Peacocke and Bealer.

There is one node left on my imagined diagram: that is the node which I want to occupy. This node represents the view that a priori knowledge is a distinctive epistemological phenomenon to be explained via some sort of conceptual approach, that we should be realists about at least some of the subject matters to be covered by the account, and that rationalism is not true.

(The fun part is fitting all those things together …)

Blogging News

Thoughts Arguments and Rants is to evolve into a group blog, and in future I'll be posting there a bit as well as here.

Jobs and Studentships

Nottingham has a three-year postdoctoral fellowship and a three-year PhD studentship available in its AHRC-funded Metaphysics in Science project.

Also, advance notice for those interested that Arché will have two five-year postdoctoral positions and two three-year PhD studentships available in its AHRC-funded Basic Knowledge project, probably to start in September 2007. (NB: I am no longer working in Arché myself; any enquiries about these positions should go to arche@st-andrews.ac.uk.)

Quine and Vague Existence: New Draft

I've posted a new draft of my paper on Vague Existence and Ontological Commitment. I got loads of feedback on this, but I've tried to keep it short and sweet ... still, if anyone thinks there's something crucial missing I'd be interested to hear!

Update: a few typos and other sillinesses now corrected!

Knowability

Another new blog for lemmings (especially modal epistemic logicians) that'll be worth following: Knowability, run by Joe Salerno.

Checking out Joe's webpage, I notice that a draft of the introduction to his collection of New Essays on the Knowability Paradox is now available, and looks to be a great overview of the current state of the debate on this topic (as well as providing some history). There is also a draft of a helpful bibliography for the volume.

They Grow Up So Fast These Days

Today is LWBM's first birthday! Thanks to everyone who's been reading and commenting and helping to make it so much fun.

New Blog for Lemmings

Berit Brogaard has just started up a new blog, Lemmings.

No Escape for Epistemicism

Some more on the argument of my previous post ...

After my paper, Daniel Elstein encouraged me to think about how epistemicists would respond to the argument. At the time, I was inclined to think they could block it, but now I'm not convinced.

Epistemicists think that (what appear to be) borderline cases for (predicate or property) F exist only due to our necessary ignorance as to where the sharp cut-off for F-ness lies. A defender of the claim that it's vague whether there are any Fs, by these lights, is committed to its being unknowable whether there are any Fs (since according to her, we can't tell where the cut-off is within a certain range, and the actual situation is somewhere within that range). But that, surely, means she lacks commitment to Fs (since in particular, she is committed to its being unknowable for her whether there are any Fs). And hence, via the Quinean criterion, we can conclude that there are no Fs in the range of her quantifiers, so the argument is up and running.

Quine and Vague Existence Again

The Joint Session was fun, although it was a shame that lots of the accommodation was so far from the conference venue - strolling in across the common was nice in the morning sunshine but at 2am it was less appealing to walk back.

Like last year, I thought the open sessions were in need of some degree of refereeing. Still, I very much enjoyed giving my paper in one of them, on ontological commitment and vague existence. The purpose of this paper (which is a much improved version of this post) is to present the following argument and then wonder what should be done about it:

1 (Quinean premise): One is committed to Fs iff there are Fs among the range of the quantifiers appearing in one's best theory.
2 (Assumption): We think it's a vague matter whether there are any Fs (and that's all we have to say on the question of whether Fs exist or not).
3 (From 2): We are not committed to there being any Fs.
4 (Contraposing on the right-to-left direction of 1, then MPP using 3): There are no Fs among the range of the quantifiers appearing in our best theory.
5 (Premise): Our quantifiers are precisely those which appear in our best theory.
6 (From 4 and 5): There are no Fs among the range of our quantifiers.
7 (From 6): We can truly assert 'There are no Fs'.
8 (From 7, disquoting): It is not a vague matter whether there are any Fs: it is settled that there are no Fs.
9 (From 2 and 8): We are mistaken.
10 (Discharging 2, using 9): If we think it's a vague matter whether there are any Fs (and that's all we have to say on the question of whether Fs exist or not), then we are mistaken.

Some members of the audience suggested that rejecting contraposition was the best thing to do, a response I've not come across before. (Although as Daniel pointed out to me later, we really only need modus tollens. But maybe the people who'd want to reject contraposition would want to reject MTT too, for similar reasons?)

Joint Session 2006

Some of my photos from this year's Joint Sesh are now online. When my feet touch the ground I'll hopefully get a couple of comments on some of the papers up here too.

Revenge of the Paranormal

I have just put a new paper online (based on stuff that I posted here a while ago). It's a short response to JC Beall's recent paper 'True, False and Paranormal'. Beall says that his five-valued semantics enables us to desribe a language which allows exhaustuve semantic characterization of its own sentences without generating liar-like contradictions. I say it doesn't!

Conference-Hopping

I'm just back from a fun conference on Moral Contextualism in Aberdeen. Some of my photos of the conference are now online. (I can assure readers that there is a perfectly rational explanation of those ones with the cutlery.)

Highlights from the conference included Berit Brogaard's attempts to convince us that the truth-value of one and the same proposition can vary with the speaker. (Her presentation is available online.) She appealed to Recanati's views on direct speech reports (whereby the quoted sentence is not merely mentioned but used) to argue that such reports, although they create shifed contexts, do not change the parameters of the circumstance of evaluation.

While I agreed that the view seems to have advantages over Macfarlane-style relativism, one thing that made me suspicious about it was that one surely wants to deliver the same result for unquoted sentences as for quoted sentences. The following pair, for instance, sounds very odd:
1. At t, John said 'Murder is wrong' and he was mistaken.
2. The sentence John uttered at t was true.
But it wasn't clear how the account could deliver this uniformity; since it appeals to special features of quoted speech to deliver the desired result in case 1, it wasn't clear how to get it for cases like 2.

John Hawthorne suggested in his talk that 'ought' claims might be subject to contextual variation in semantic value for the same reasons as are the 'can' claims which they (supposedly) imply. This, I thought, might sit quite well with the view (suggested in Lewis) that there is contextual variation in the semantic value of modal utterances due to contextual restriction of the quantifiers over worlds which they involve.

I was particularly interested, therefore, to hear Ralph Wedgwood developing a version of Angelika Kratzer's possible-world semantics for 'ought' claims in the next-but-one session. Kratzer's basic idea here (subject to many bells and whistles, of course) is that context supplies a set of propositions which are held fixed across all relevant worlds, and an ordering on those worlds. 'It ought to be that p' is then true iff p is true in all the worlds ranked as unsurpassed.

Tomorrow I'm off to Southampton for the Joint Session, so more paper reports should follow soon.

Williamson on Conceptual Truth

Tim Williamson has a paper on Conceptual Truth in the new Aristotelian Society Supplementary Volume. His target is the view that appealing to something like conceptual truth or analyticity can help us explain how a priori knowledge works.

But strangely, he focuses almost exclusively on one particular - and particularly weak - version of this type of view. Almost the entire discussion is concerned with the view that anyone who understands a conceptual truth knows it. I don’t know of any contemporary philosopher of the a priori who defends this claim, and indeed it is not attributed to anyone by Williamson. Although in footnote 5 Williamson claims that Boghossian holds ‘something like’ it, I doubt whether Boghossian would accept this reading of his work. Peacocke is also mentioned, but as I understand him Peacocke is not committed to anything in this vicinity either. The same footnote also says that ‘the focus of this paper is not on some few thinkers in particular; it aims to make explicit and criticize a conception on which many contemporary philosophers still rely, often tacitly, at various points in their work.’ But the paper would be more exciting if its took into account some of the potentially interesting versions of the conceptual approach currently being proposed by serious philosophers of the a priori. There is too much of the straw man about the view Williamson actually discusses. Even some examples of places where he thinks this view is being assumed by philosophers who are not specifically interested in the a priori would have helped to motivate the paper.

The only attempt to engage with slightly more sensible versions of the conceptual approach is fleeting: on pp. 26-7 he considers the view that understanding merely puts one in a position to know or justifies the relevant belief. He argues that some people who understand the relevant propositions aren’t even in a position to know them, because certain of their other commitments get in the way of their believing them. This may or may not be the best way of describing these cases, but even if it is, it isn’t particularly devastating: a nearby position which Williamson doesn’t consider is the view that whoever understands certain propositions and believes them on the basis of that understanding knows them. Not that I would defend anything like this view myself - my point is just that Williamson's arguments do nothing to touch it. (Moreover, the debate on, for instance, how Boghossian’s view fares with regard to the distinction between possessing knowledge and having a warrant available to one is already at a more advanced stage than Williamson’s discussion takes account of - see Philip Ebert’s 2005 paper on this point).

Also, the argument in this section relies heavily on assumptions I think are false, e.g. that ‘justification rather than knowledge is the central epistemological question only for internalist theories’ (p. 27). Justification, like knowledge, can be construed in an externalist or an internalist fashion, and an externalist about both notions could well take justification to be the, or at least a, central epistemological notion.

A good point is mentioned on p. 4, namely that conceptual approaches tend to assume the epistemological problem of a priori truth is somehow ‘automatically’ solved for conceptual truths, but they ‘do not say how it is solved’. This point, however, is anticipated (and developed in more sophisticated ways) in various places, including e.g. Field 2005 and BonJour 1998.

Williamson's discussion, which focuses on finding counterexamples to the view under consideration, does not take the most illuminating tack in attempting to show what's wrong with it. What's more illuminating is the fact that even if it were true that everyone who understood a certain proposition knew it, we still wouldn't have given any account of how they knew it.

Against 'Against 'Against Vague Existence''!

Robbie Williams has a response to my post Against 'Against Vague Existence' over on his blog Theories 'n Things.

I've recently written up a short note based on the idea in my original post, which I've put online here. I hope it goes some way to addressing Robbie's concerns (which centre on the thought, shared by Sider, that I need to say something about what kind of thing a precisification is on the envisaged account).

Extended Simples and Quantized Space

David Braddon-Mitchell and Kristie Miller have a fun new paper arguing that we can both believe in spatially extended mereological simples and agree that every extended object o has a part at each sub-region of the region which o occupies. The trick which is supposed to enable us to marry these two theses is to claim that space has smallest regions which have no sub-regions. (This is a position I've heard defended in conversation by others as well, so I'm coming round to the view that it ought to be taken seriously.)

For many of us, quantized space seems a very strange idea on the face of it, but Braddon-Mitchell and Miller argue that it must be taken seriously because of certain results in physics. They claim that 'physicists tell us that we cannot divide up space into any finer-grained regions than those constituted by Planck squares [i.e. areas of 10 to the power -66 centimetres squared]' and that physics 'tells us that talk of space breaks down altogether once we talk about regions smaller than the Planck square'. 'Hence', they conclude, 'we know that talking about something occupying a sub-region of a Planck square makes no sense: there is no such sub-region' (p. 224).

When they give a few details of what the physics actually shows, it turns out to be that 'there is nothing that could be taking place within these squares'. Braddon-Mitchell and Miller take it (and this is where I get puzzled) that this 'is to say that in principle, there cannot be anything that occupies the sub-regions of such a square' (p. 224, their emphasis).

For all I know, physicsists may well be claiming this sort of import for that sort of result, but I can't see how the transition could be that straightforward. What I can't understand is how any claim about what can or cannot take place with a Planck square - which is of course the sort of thing physicists can helpfully tell us about - could settle the question of whether such a square has sub-regions. Specifically, I wonder what sort of results are supposed to distinguish between the hypotheses:
1. that Planck squares have no sub-regions
and
2. that any Planck square (and therefore any sub-region of a Planck square) must, as a matter of nomic necessity, be uniformly filled.

The claim that nothing can be 'taking place' within a Planck square seems at best to get us as far as 2. What justifies the further step to 1? What sort of result from physics as it is currently practiced could possibly justify this further step?

(I ask these questions in self-confessed ignorance of the physics, but with a dose of scepticism as to whether we can get this much metaphysics out of it, whatever it is!)

Job News

I've just accepted a job offer from the University of Nottingham. I start there on 1st September, although I will be in Australia until September 2007.

My favourite colleague is also moving to Nottingham. We are sorry to leave behind lots of great colleagues in St Andrews, but are very excited about joining the Nottingham crowd!

Philosophy of Flirting

Just for fun, I've written up a few thoughts on the philosophy of flirting. I'm trying to make progress towards a set of necessary and sufficient conditions for when an act of flirtation has taken place. Let me know what you think!

TAR at new address

For those who read Brian Weatherson's blog as well as this one (I imagine an improper subset of those who read this blog), Thoughts Arguments and Rants is now at http://tar.weatherson.org/ after the original address was hijacked.

They'll All Be Concept-Grounding Theorists Soon ...

More evidence that a priori knowledge is hitting the big time again - and that people are starting to ask just the right sorts of questions about it (that is, the questions that motivate my view ... :)

Infallibility and Modal Epistemology

The Arche Modality Conference has just finished, and has been excellent fun. I've put some photos on my website. In the end, my comments on Scott Sturgeon's talk mainly focussed on the claim that the infallibility of idealized conceivability methods is the wrong focal point for his worry. He's worried that if we are realists, we shouldn't think that metaphysics and epistemology will fit together the way the infallibilist requires - there should be room to make a mistake. For idealized conceivability (as he thinks of it) involves only mental idealization (allowing unlimited time, capacities etc.). How can we have a guarantee of getting a true belief, if we have only idealized these mental processes, and said nothing about their relationship to the world?

But I argued that we still have a worry of the same kind for fallibilist conceivability views. My point here was just an analogue of what we tell students who think Hume’s worries about induction show that we aren’t guaranteed to get true beliefs by inductive methods, but still think these beliefs are likely to be true. What I claimed is that, for the same reasons Sturgeon thinks we should be worried about the infallibility of conceivability, namely because epistemology and realist metaphysics don’t fit together like that, we should also be worried about the claim that it’s likely that conceivability will deliver true beliefs. Epistemology and realist metaphysics don’t fit together like that either – you don’t get good ways of finding out about the independent world when you idealize along only mental dimensions. Good ways of finding out about the independent world require input, which is a world-involving relationship, and not purely mental.

So infallibility is not necessary to generate the problem. In fact, I claimed, it’s not sufficient either. Sturgeon’s worry will go away if we can somehow add a mind-world input element into our account of ideal conceivability. This sort of ideal conceivability can unproblematically be infallible, for the same reasons Sturgeon thinks idealized vision (which is, among other things, always veridical) can unproblematically be infallible.

The deep problem in the vicinity of Sturgeon's worry is a very old one: how can a priori reflection be a source of knowledge of facts which are construed realistically? But of course, there are many answers to this and debates about them which would have to be engaged with before we could claim to have pressed the point in a new way.

Responding to Kripke

Right, I'm back ... minus one appendix. And straight back into the thick of it, with the Arche academic audit starting today. We've had talks by Mark Sainsbury, Paul McCallion, Philip Ebert and Marcus Rossberg (jointly) and Frank Jackson, with topics ranging from famous fictional characters such as Sherlock Holmes to infamous real ones such as Julius Caesar and Timothy Williamson.

In my spare time :) I'm meant to be preparing some comments on Scott Sturgeon's talk at the upcoming Modality Conference, which is based on this paper. He is arguing against the following combination of views:

1. Kripke is right that ideal conceivability does not imply possibility.
2. But we should make minimal adjustments to deal with 1 - i.e. we should hold that ideal conceivability implies possibility except in the particular kinds of case Kripke brings to our attention.

One thing I'm not sure of is whether this combination of views is defended in print by anyone. (Scott doesn't mention anyone in the version of the paper I've seen.) But more interestingly, I wonder whether many people really (perhaps tacitly) think this is the appropriate thing to do.

Out of action

LWBM will probably be off air for a little while; due to illness I will be off work until at least the end of May.

Going to Australia

I'm very pleased to be spending the next (British) academic year on secondment at the ANU. I'll be working on an ARC project, Epistemic Warrant, lead by Daniel Stoljar, Martin Davies and Crispin Wright. The project will focus on transmission of warrant, basic knowledge and entitlement.

Dogmatism and The Content of Experience

If I understand correctly (and I'm indebted to Sebastian Schmoranzer's recent Arche presentation for clarifying the following exegetical points) it is a tenet of Pryor's dogmatism (as represented in this paper) that certain of my experiences give me a reason to believe I have hands, and this regardless of any antecedent warrant I may have for thinking that I am not hallucinating, not a brain in a vat, etc.. Why? Because my experience represents it as being the case that I have hands.

However, my experience's 'representing it as being the case that I have hands' cannot amount to its being as it would be if I had hands, lest we be able to construct a parallel argument to the effect that experience gives me a reason to believe I am a brain in a vat being fed perfectly hand-like sensations.

The standard response to this seems to be that although my experience is as it would be if I were that kind of brain in a vat, my experience does not represent it as being the case that I am that kind of brain in a vat in the way it represents it as being the case that I have hands. That is, the content of my experience is that I have hands, not that I am a brain in a vat having hand-like experiences.

This seems to raise a puzzle: how do we spell out the notion of content required? If it is purely something about (my relationship to) the external world that makes the difference between having an experience with content 'I have hands' and having an experience with content 'I am a brain in a vat having hand-like experiences', then the 'standard response' just described appears to collapse the dogmatist line into a familiar kind of disjunctivist response to scepticism.

On the other hand, suppose we try to use inferential role (assuming that to be something internally accessible) to distinguish the two contents. Then the important thing about the inferential role of the content of the experience I'm actually having is presumably going to include things like the fact that I can correctly infer from the content of this experience to the conclusion that I am not a handless brain in a vat, which is something I cannot infer from the content of an experience which represents it as being the case that I am a brain in a vat having hand-like experiences.

However, it seems to be blantantly begging the question against the sceptic to assume without further comment that I am presently having an experience the content of which enables me to correctly infer that I am not a handless brain in a vat. This is exactly what the sceptic doubts my experience is like.

So what other stories about the difference in content are available for the dogmatist to tell here?

Against 'Against Vague Existence'

In 'Against Vague Existence', Ted Sider argues that our quantifiers cannot be vague, because it is impossible to characterize semantic vagueness in our quantifiers in the usual way; that is, in terms of multiple admissible precisifications. Sider considers as a test case whether it could be indeterminate, due to vagueness in the existential quantifier, whether the following was true:

(E): Ex (x is composed of the F and the G).

Sider claims that the ‘familiar model’ for spelling out how such indeterminacy comes about would apply to this case as follows:

(P1): ‘E’ has at least two precisifications, call them E1 and E2. There is an object, x, that is in E1’s domain but not in E2’s domain, and which is composed of the F and the G. Thus, (E) is neither definitely true nor definitely false.

But, as Sider points out, ‘the defender of vague existence thinks that it is not definitely true that there is something composed of the F and the G ... She will therefore not make this speech’ (p. 139).

Sider proceeds to offer three options to the defender of vague existence: rejecting the need to non-vaguely describe the precisifications, using vague quantifiers to non-vaguely describe them, and finding non-quantificational non-vague language to describe them. None of these is my preferred way of resisting Sider’s argument. Nor do I wish to resist (here) his two presuppositions: that the indeterminacy of (E) would have to be semantic (as opposed to ontic), and that this means we need to explain it in terms of multiple admissible precisifications of the existential quantifier.

Instead, I propose we investigate how much can be achieved through paying careful attention to scope in describing the relevant precisifications. Instead of (P1) above, perhaps we can appeal to:

(P2): ‘E’ has at least two precisifications. On the first precisification, there is an object, x, which is composed of the F and the G. But on the second precisification, there is no such object. Thus, (E) is neither definitely true no definitely false.

Note that, now, the existential quantifiers appearing in the account of why (E) is neither definitely true nor definitely false occur within the scope of the operators ‘on the first precisification’ and ‘on the second precisification’. Hence there is no need for any metalanguage commitment to an object which is composed of the F and the G.

(P2) seems to do what Sider requires: it talks about two precifications for ‘E’, and explains what it is about these two precisifications which results in the indeterminacy of (E). So what’s wrong with (P2)?

Field Motivates Concept Grounding

In his paper 'Recent Debates About the A Priori', Hartry Field seems to me to be spot on the following passage (pp. 13-14 of the online paper):

[T]he key issue is ... : why should the fact, if it is one, that certain beliefs or inferences are integral to the meaning of a concept show that those principles are correct? Why should the fact, if it is one, that abandoning those beliefs or inferences would require a change in meaning show that we shouldn't abandon those beliefs or inferences? Maybe the meaning we've attached to these terms is a bad one that is irredemably bound up with error, and truth can only be achieved by abandoning those meanings in favor of different ones ...

However, I don't agree with Field that this point is a step on the way towards his conclusion, namely that to claim we have an entitlement, at least in the case of 'basic' beliefs or logical rules, is merely to express an attitude of approval toward those beliefs or rules.

Rather, what Field's questions rightly raise to notice is the need for some account of why we should trust the meanings we have attached to our words (or, as I would prefer to say, why we should trust the concepts we express by them) to serve as epistemic guides to the way the world is. That is, we need a story about concept grounding to explain why these meanings or concepts are rightly taken as encoding information about the world which we can recover through introspection.

Beall and the Paranormal

This week I've been thinking about JC Beall's fun paper 'True, False and Paranormal'. Essentially, the idea is to model our truth-talk with a disquotational predicate 'T', and have a language which can exhaustively characterize all its sentences as 'true', 'false' or 'other', without thereby admitting true contradictions. Sentences of the model can take any one of five values, 0, .25, .5, .75 and 1, of which .75 and 1 are designated. A new term 'pi' is introduced (sorry I don't have a pi-symbol here!) to mean 'paranormal' (or 'other'), and pi-A takes the value .75 when v(A) = .25, .5 or .75, and takes the value 0 otherwise.

It seems that the view requires that there is no predicate in the model language like D ('D' for 'designated'), where:
v(D[A]) = 1 or .75 when v(A) = 1 or .75
and v(D[A]) = 0 or .25 when v(A) = 0, .25 or .5

Otherwise the sentence
A*: ¬D[A*]
presents a problem. (It is designated iff it isn't.)

But it seems to me that such a predicate is needed in order for the model language to be capable of expressing claims about its own semantic machinery (that is, capable of expressing the designation stuff that we can talk about in the metalanguage). Nothing else will do; in particular, any predicate D' such that the value of D'[A] is .5 when the v(A) = .5 does not express designation; any designation claim must take value .25 or less when v(A) = .5.

Why? Because .5 is not a designated value. Of course, that only means its true-in-real-life that .5 is not designated, which you might want to say does not imply that the value of D[A] should be an undesignated value. Truth-in-real-life (as JC has helpfully stressed to me in conversation) is not supposed to be modelled by designation but by truth-in-the-model (i.e. the behaviour of 'true' in the model).

But I think in order for our D to express designation we need D[A] to be false-in-the-model when v(A) = .5, which (unless I'm missing something) means we want F[D[A]] to be designated when v(A) = .5, i.e. we want T[¬D[A]] to be designated, which can only happen if ¬D[A] is designated, which in turn requires that v(D[A]) be at most .25 (because in this model negation toggles designated values with values of at most .25).

If Beall is saying that no model is capable of expressing these things he seems to be forced to say either that no model is adequate as a model of English, which can talk about its own semantic machinery, or that, like the models, English cannot express claims about its own semantic machinery.

If one says the first thing, then one has to admit that these models can't help us understand the Liar - after all, the Liar arises because English can express claims about its own semantic machinery, and if the models don't model this feature of English, they are irrelevant to the Liar. (This point relates to Beall's claim to have preserved exahustive characterization: the exhaustive characterization we wanted was an exhaustive characterization of all the sentence in the model in terms of their semantic values, but we didn't get that.)

And familiarly, if one says the second thing, one places an implausible limitation on the expressive powers of English.

UConn

I’ve just got back from the University of Connecticut, where I gave my paper on Modal Knowledge at the Philosophy Department Colloquium and got lots of helpful feedback. The UConn grad students have just started a blog, What Is It Like To Be a Blog?.

I also attended a conference on Conditionals. On Saturday, Dorothy Edgington told us what she thinks about subjunctive conditionals, namely that they do not have truth values but rather express the speaker’s belief that the conditional probability of the consequent on the antecedent is high (i.e., basically, they function pretty much the way she thinks indicatives do, but in a different tense).

I was worried that there seem to be cases where the consequent is unlikely to be true given that the antecedent is, yet still would be true if the antecedent was. The existence of such cases suggests that subjunctives and conditional probabilities are not correlated in the way Edgington claims. We discussed the following example (one suggested by Edgington when I raised my worry in discussion time). Suppose you decide at the last minute not to get on a plane which is very unlikely to crash, and the plane in fact crashes, killing all its passengers. It’s tempting to think that the probability of your dying conditional on having got on the plane is low, because the plane’s chances of crashing were low, yet clearly if you had got on the plane you would have died.

Edgington replied that we simply have to find the right conditional probability, in much the same way that (say) someone who likes closest-world semantics for these conditionals has to find the right similarity relation. In the above case, she said, the right conditional probability is that of your dying given that you got on the plane and it crashed. To save the proposal, you just need to find the right pieces of further information about the world to take into account, besides what is mentioned in the antecedent. This information will makes the conditional probability of the consequent high.

This might be thought to be a bit ad hoc, given that the crashing is not mentioned in the antecedent of the conditional we’re actually interested in. But regardless of that, I think it is a problem that the response won’t always work if there is indeterminacy in the world. For in that case, there will – or at least, could – be some unlikely events that just happen, and are not rendered any more likely however much further information about the world we take into account.

Suppose C is an event that would have happened, without being determined, if A had happened, although it was very unlikely to do so. Then the subjunctive:
If A had happened then C would have happened
looks true, although the conditional probability of C on A is low. And in this case there is no further information about the world that we can take into account which will make the conditional probability of C high – that is, there is nothing which can play the role played by the fact that the plane crashed in Edgington’s response to the first example.

So Edgington’s account of counterfactuals seems at risk of giving the wrong results unless we assume there is no indeterminacy. And this seems to be a distinctive problem for the account, not analogous to an problem faced by closest-world approaches.

Time Travel and Backwards Causation

It seems to be quite widely assumed (I am informed, by sources who read more about this sort of thing than I do) that backwards time travel requires backwards causation. It wouldn't suffice for time travel if in 2015 I climbed into a time machine and someone looking and acting exactly like how I look in 2015 came into existence for no apparent reason in 1926. Rather, that person's turning up in 1926 would have to be caused by my actions in 2015.

I agree with the insufficiency claim. But I'm not sure whether the causal requirement is motivated by it. (I'm also hung up on whether it might be a conceptual truth that causation happens forwards, not backwards, but let's not worry about that.) Wouldn't it be enough if there were the right kind of non-casual explanation of this person's turning up in 1926, in terms of my actions in 2015? If not, why not?

(I am concerned that I will be trussed up in a sack and sent back to Cambridge for posting on this, but I'm going to do it anyway ...)

Basic Knowledge Workshop: Call For Graduate Papers

I'm organizing an Arché workshop on Basic Knowledge, which will take place on 24-25 November 2006. Speakers will include Jason Stanley, Duncan Pritchard, Jessica Brown and Timothy Williamson. There will be a slot for a graduate student paper. Graduate students, and those who obtained their PhDs within the last twelve months, are invited to submit papers of not more than 5000 words. Please send me submissions as email attachments in Word or similar format (no pdf files please). Suitable topics include: Sceptical Paradox, Transmission and/or Closure, Non-Evidential Warrant, Internalism and Externalism, and A Priori Knowledge. Particularly welcome are papers which open up new areas of enquiry within these fields, and/or highlight directions in which further research is needed. Travel and subsistence will be covered by Arche for the author of the selected paper. The deadline for submissions is 31 August 2006.

ADDENDUM: Submissions should be prepared for blind review.

Counterfactuals and Ontic Vagueness

Following on from the idea I floated in this post, I'm posting a draft of a note on why you shouldn't use counterfactuals to characterize commitment to ontic vagueness (which won't surprise those who know that I tend to think you probably shouldn't use counterfactuals to characterize anything metaphysically interesting ...). Comments very welcome, as always.

Lewis/Blackburn Again

A slightly improved draft of the Lewis/Blackburn note is here.

Weighing Implausibilities

Here's something I was wondering about during Tim Williamson's talk at the Arché Vagueness Workshop yesterday.

Suppose you want to keep bivalence, and you also think that the only way for something to be an aspect of a predicate's meaning is for our use of the predicate to determine that it is (both Williamsonian thoughts, I gather). But you also think it is at least prima facie implausible that usage determines an exact cut-off point for all the vague predicates (a thought pressed against Williamson by McGee and McLaughlin).

We seem to have at least two options.
1: Accept the implausible-sounding claim (with Williamson), or
2: Argue that many of the things we think are vague predicates ('red', 'bald' etc.) are in fact not predicates at all. By bivalence, in order for them to be predicates we would need there to be cut-off points for their application. But it is implausible that our use of these terms determines such cut-off points. And there is nothing else which can do this sort of meaning-constituting work.

It's initially implausible, sure, that words like 'red', 'bald' and so on are not predicates. But my question is: by what sorts of methodological considerations do we weigh this implausibility against that of the claim that usage determines cut-off points for all such terms?

(Incidentally, Williamson mentioned that he talks about Option 2 in his book on vagueness, which I haven't had a chance to look at yet. He obviously has reasons for preferring Option 1, which I will be interested to read.)

Lewis/Blackburn Note

I wrote up some thoughts relating to my previous post as a short note. Comments welcome!

Quasi-Realism No Fictionalism (But Not Quite For Blackburn's Reasons)

I've just been leading the MRG on the Lewis/Blackburn exchange in this collection concerning whether quasi-realism is fictionalism (Blackburn's half of which is online here).

It seems to me that Lewis's claim that quasi-realism is a version of fictionalism is mistaken, but not for a reason that comes through in Blackburn's response.

Lewis's argument, in essentials, is that the quasi-realist wants to say everything the realist does, so must either be a realist or be making believe that realism is true. But he is not a realist, therefore he is making believe that realism is true, i.e. he's a fictionalist.

I think we can show what's wrong with that argument in a few lines. The sense in which the quasi-realist 'says everything the realist does' is not the one which enforces either being or pretending to be a realist. This would be enforced if the quasi-realist was making the same assertions as the realist, but he isn't (indeed, the paradigm quasi-realist isn't making assertions at all). The quasi-realist says things which sound like what the realist says, but they are to be interpreted differently - in the moral case, as expressions of attitudes, rather than as committing to moral properties. Expressing an attitude requires neither belief in moral properties (realism) or pretense that moral properties exist (making believe that realism is true).

So here's why quasi-realism is not fictionalism:
The fictionalist differs from the realist in adopting the realist account of the meaning of the target sentences but dissenting from those sentences (same content, different attitude) whereas the quasi-realist differs from the realist in adopting a different account of the meaning while continuing to accept those sentences (different content, same - or at least similar - attitude).

Entitlement and Rationality

My paper on Crispin Wright's notion of Entitlement is now also up - though NB still in draft form - on my home page. Comments welcome on this too!

Knowability Again

I've just posted the final draft of my knowability paper on my home page. Comments are still welcome!

New Arche Blog

Arche now has a blog on which all Arche members can create posts. The aim is to encourage philosophical interaction between Archeans and friends around the world. We also welcome participation from other philosophers - comments are publicly open.

Cook on Unknowability

Roy Cook has just argued that there are some unknowable propositions provided it is possible for the following situation to obtain. Ava, Brigitte and Dorothy are all inhabitants of Smullyan’s (1978) island occupied solely by knights and knaves. Knights are people who always speak truly, knaves are people who always speak falsely. Simultaneously, they utter the following:
Ava: What Brigitte is now saying cannot be known to be true
Brigitte: What Dorothy is now saying cannot be known to be true
Dorothy: What Ava is now saying cannot be known to be true

Cook shows that if this happens then at least two of Ava, Brigitte and Dorothy must be knights (see his p. 12), and goes on to show as a consequence of this that at least one of them – we do not know which one – has uttered a true but unknowable proposition. He assumes classical logic and certain facts about the behaviour of the knowability operator in order to get this result, all of which we can grant here for the sake of argument.

Cook stresses that his argument relies on the thought that the scenario he describes is free from ‘any paradox, failure of reference, or other pathology’ (p. 14). It seems to me, however, that the anti-realist who accepts the principle p --> Kp will think Cook’s scenario is paradoxical, because it presents a version of the paradox raised by what Cook would call the semantic open triple (sorry, no corner quotes):
p: ¬Tq
q: ¬Tr
r: ¬Tp
(where T is the truth predicate). No assignment of (classical) truth values to these three propositions is consistent.

Anti-realists for Cook’s purposes are those who accept that if p then p is knowable, which Cook represents as p --> Kp, the contrapositive of which is ¬Kp --> ¬p. By this and the contrapositive of disquotation for the truth predicate, ¬p --> ¬Tp, these anti-realists will also accept that ¬Kp implies ¬Tp. Hence the three characters in Cook’s story are uttering claims which are either stronger than or identical in strength to the paradox-creating claims of the semantic open triple. In fact, anti-realists will presumably think the claims are identical in strength; for they are happy to accept ¬Kp --> ¬Tp, and ¬Tp --> ¬Kp is trivial.

One might respond that this is to beg the question; the only reason that is being offered for thinking that Cook’s situation is paradoxical is adherence to p --> Kp, which, of course, one does not accept unless one is an anti-realist.

But we need to be clear about where the burden of proof lies. Cook is (tentatively) offering an argument that should be capable of persuading anti-realists that there could be an unknown truth. To do this, as he acknowledges, the situation he describes should not be paradoxical. But the anti-realist will think it generates a Liar-like paradox, namely the semantic open triple. Therefore Cook’s argument will not be persuasive to an anti-realist.

I Wanna Have Control

Here's a point that came up recently following a talk by Arché visitor Dean Zimmerman on Molinism.

It can't be sufficient, to count as having control over someone else's actions, that their actions vary counterfactually with yours - that were you to F they would F, and were you to G they would G, etc.. For if this were the case we could have symmetric control. It might also be that were they to F you would F too, and so on. (Suppose that, necessarily, you F iff they do.) But you can't each be controlling the actions of the other - control is an asymmetric relation.

So what do we need in order to explicate the notion of control? It doesn't help to specify that exactly one of them is aware of the counterfactual relationship between his actions and the other guy's, and say the controller is the one who's aware. For one can perfectly well be aware that one's actions are being controlled by someone else (who is not aware of the fact).

Unsurprisingly, I think what we need to appeal to here is probably explanation. What matters is whose actions explain those of the other. You are in control just in case your actions explain the other guy's. Explanation brings with it the right kind of asymmetry, as well as making sense of the feeling that the controllee's actions depend upon the controller's.

Knowability

I'm just about to start work on the final draft of my new paper on Fitch's Knowability argument, so I'm posting the current draft here to invite comments. The earlier Fitch paper of mine which I refer to can be found here and the forthcoming Kvanvig paper I talk about is online here.