The Parochialism of Metaethical Naturalism

I've previously suggested that naturalism can't account for substantive boundary disputes (and I mean to turn that into a proper paper sometime soon).  But as I've been working on my Moral 2-Dism paper I've found another sense in which metaethical naturalism entails a troubling kind of parochialism.  It's this: to avoid the Open Question Argument, naturalists now hold that there is an a posteriori identity between certain moral and natural properties (on the model of water and H2O).  This entails that moral terms are 2-D asymmetric, i.e. have differing primary and secondary intensions.  This in turn means that what our moral terms pick out at a world may differ depending on whether we consider the world 'as actual' or 'as counterfactual'. But this is objectionably parochial: (our assessments of) the moral facts should not differ depending on our location in modal space.

The 2-D Argument Against Metaethical Naturalism

A few years back I noted that 2-D semantics provides a straightforward refutation of synthetic metaethical naturalism (SEN):  SEN implies that moral terms differ in their primary and secondary intensions, this is clearly false (moral terms are "semantically neutral", or exhibit 2-D symmetry, in that their application to a world does not vary depending on whether we consider it as actual or as counterfactual), and so SEN must be false.

As I've been developing this argument in my paper 'Moral Symmetry and Two Dimensional Semantics', it occurs to me that 2-D semantics enables an even broader argument against metaethical naturalism.

Moral Judgments, 2Dism, and Attitudinal Commitments

There's an interesting new paper in Ethics, Moral Realism and Two-Dimensional Semantics by Tim Henning, which offers a lot of opportunities for disagreement. The abstract:

Moral realists can, and should, allow that the truth-conditional content of moral judgments is in part attitudinal. I develop a two-dimensional semantics that embraces attitudinal content while preserving realist convictions about the independence of moral facts from our attitudes. Relative to worlds “considered as counterfactual,” moral terms rigidly track objective, response-independent properties. But relative to different ways the actual world turns out to be, they nonrigidly track whatever properties turn out to be the objects of our relevant attitudes. This theory provides realists with a satisfactory account of Moral Twin Earth cases and an improved response to Blackburn’s supervenience argument.

There are some clever formal moves in the paper, but on a substantive level it does not strike me as very promising. Here's why...

The Open Question Argument

I'm sympathetic to the old-fashioned idea that reflection on normative concepts suffices to see that metaethical reductionism is a non-starter. I recently sketched a "normative Knowledge Argument" along these lines, but of course the most famous argument in this vein is Moore's Open Question Argument.

Representational Content

The notion of 'content' is a bit mysterious to me, but I gather it is meant to be what is represented by a sentence or thought -- some or other proposition, perhaps. When you say, "I agree with what he said," you are affirming the content of the other's utterance. It may also be how we individuate beliefs, i.e. we will say 'they have the same beliefs' just in case their beliefs have the same contents.

These contents may be modelled as sets of possible worlds, but this will yield very different results depending on which dimension we use, i.e. whether we settle on primary or secondary intensions. When two distinct people each proudly declares, "I have ten toes," their utterances have the same primary intensions (being true for any world centered on a ten-toed person), but different secondary intensions (being true just in case that very speaker has ten toes). So should we say they have the same content, or not? Both answers seem partly correct - there is a sense in which they believe the same thing, and a sense in which they differ - I guess this is just the distinction between narrow vs. wide content.

Here's an argument for wide content: we sometimes talk of beliefs in such a way as presupposes that each has a single, absolute truth value (within a single possible world). If two people believe the same thing, it can't be that one of them is right and the other is wrong. A proposition is either true or false, not true for one person and false for another. Indexicals are explained away on this picture by suggesting that they really contribute different representational content in either case. 'I' in my mouth serves to represent me, whereas your use of 'I' represents you. So we are talking about different things (different people) when we use these words. The content of what we believe/say is not the same after all.

Here's an argument for narrow content: we want representational content to capture how we take the world to be - i.e. which possibilities, if actual, would render our belief true. (Frank Jackson talks about 'worlds whose actuality is consistent with the truth of S.' Note that this is different from 'the worlds at which S is true', due to rigid designation and other 2-D quirks.) This is the commonsense notion of content that is introspectable, closely tied to cognitive significance, and otherwise guides our inferences and behaviour.

For a more theoretical motivation, we may think that the content of a belief is the set of worlds we distribute credence over. To borrow an example from Jackson, consider how your belief that Paris is pretty maps onto the following picture of logical space:

Let 'the D' be the unique associated description by which I identify Paris, i.e. the primary intension of 'Paris'. This description is satisfied by different objects (X1, X2, etc.) in different worlds. Only one of these Xs is actually Paris, but - since I don't know which world I'm actually in - I don't know which one.

Now, in believing that Paris is pretty, I distribute my credence over all those worlds where the D is pretty. That's the shaded circle. Note that I do not distribute my credence over all the worlds where Paris, that very object (X1, say), is pretty -- because, firstly, I do not know that Paris is X1, and secondly, I do know that it won't actually come apart from 'the D' that fixes its reference. So my credence is spread over the circle of worlds where the D is pretty, rather than the worlds where X1 (Paris itself) is pretty. So I guess that's Jackson's second argument for descriptivism.

Can Railton Avoid the Conditional Fallacy?

In 'Moral Realism' (1986), Railton suggests a form of ideal agent theory (of one's non-moral good) designed to avoid the conditional fallacy:

Give to an actual individual A unqualified cognitive and imaginative powers, and full factual and nomological information about his physical and psychological constitution, capacities, circumstances, history, and so on. A will have become A+, who has complete and vivid knowledge of himself and his environment, and whose instrumental rationality is in no way defective. We now ask A+ to tell us not what he currently wants, but what he would want his non-idealized self A to want - or, more generally, to seek - were he in the actual condition and circumstances of A. (pp.173-4, bold added.)

In class yesterday, Dave came up with a wonderful example to suggest that even this double-counterfactual creates interference. Suppose that A's strongest desire is that his cognitive capacities never decline. He desires that, if at any future moment he becomes stupider than he previously was, he dies. (This is just a more extreme version of the common preference many of us have to die rather than succumbing to Alzheimer's or similar mental degeneration.) Given Railton's merely instrumental conception of rationality, there's no reason why this desire couldn't survive idealization, and so be shared by A+. But now the indexical character of the desire is latching on to a new content, given by A+'s context rather than A's. Given that A+'s strongest desire is to be no stupider, what he would want were he to find himself "in the actual condition and circumstances of A" is simply to die! This clearly does not reflect what is in A's objective interest at all, since A has not actually suffered any degeneration. The problem is merely an artifact of the counterfactual scenario.

Liz Harman then suggested a couple of clever solutions. The problem, recall, is that the counterfactual context changes the content of A's indexical desires. So one solution would be to construct the idealization according to the (actual) content rather than character (meaning) of A's desires. That is, even in the idealized context, we treat the desires as referring to A and his actual circumstances. Then A+'s strongest desire is merely to be no stupider than A.

A second option, which I like even more (though I'm not sure how much of it is a reconstruction on my part) would be to bring A's context over to A+. That is, ask A+ to assess an indicative rather than subjunctive conditional: not "what would you want if you were to find yourself in A's condition", but "under the hypothesis that you are in A's actual condition, what do you want?" (Very 2-D!) I think that should work, right?

(Mind you, it's a bit of a mystery why Railton appeals to this idealization process at all. Given that he only builds in full information + instrumental rationality, it doesn't seem that A+ is allowed to revise any of A's ultimate ends. So what work is he doing? Why not just directly identify A's objective interest with whatever would best fulfill his ultimate desires in fact? Presumably that's what is supposed to be guiding A+'s decision. Smith mentioned Railton's "wants/interests mechanism" as going beyond mere instrumental rationality, by tending to bring our motivations more into line with our affective responses, but this alignment does not seem to be included in the idealization process quoted above. Can anyone think of a case where A+ would appropriately choose something other than what would best fulfill A's ultimate desires? Divergence - as in the 'degeneration' case above - seems to indicate precisely that the idealization has gone wrong!)

Thesis Conclusion [draft]

[The concluding summary of my honours thesis. Links to the earlier chapters are interspersed with the text...]

It’s natural to expect that what can be known without needing to look at the world is closely tied to how the world metaphysically could or must have been. If we can only learn a fact a posteriori, through empirical investigation, we may expect that this is because there are other possible worlds in which the fact in question fails to hold. Assuming that possible worlds are wholly self-contained, we would not expect that examining the actual world could tell us anything informative about other, non-actual possibilities. Modal rationalism draws on these intuitive ideas by positing an intimate link between apriority and necessity, according to which an ideally rational agent could in principle grasp modal space – or apprehend what is possible and what is not – through the exercise of reason alone.

Kripke’s discovery of the necessary a posteriori casts doubt on this picture. There are some necessary truths – e.g. ‘water is H2O’ – which can only be known after empirical investigation. But the modal rationalist suggests that the problem here is merely semantic. We can know a priori how all the various possible worlds are in themselves; what we don’t always know is how to apply our words to them. Some terms, like ‘water’, are not semantically neutral – their application to counterfactual worlds is contingent on how the actual world turns out. That’s why empirical inquiry may be required before we can accurately assess various modal claims. The extra work is required to grant us semantic, not metaphysical, knowledge. We may avoid this need by restating a claim in neutral terms, for which the semantic values are unaffected by whether we consider a world “as actual” or “as counterfactual”. Chapter One thus established that the Kripkean challenge to modal rationalism is toothless after all; the link between apriority and necessity may be restored by restriction to semantically neutral vocabulary.

What’s needed to refute modal rationalism are “strong necessities”, i.e. claims that are true in all worlds considered as actual, despite being conceivably false. This requires that there be coherent scenarios that would not be verified by any possible world. Chapter Two explored this idea further, and assessed Yablo’s arguments for the claim that modal rationalists must recognize such strong necessities. Arguments from meta-modal conceivability provide the greatest challenge here, but I proposed that modal rationalists should respond by treating scenarios as epistemically fundamental, so that meta-modal conceivability is then uniquely determined by the sum of individually conceivable scenarios. Other arguments assume that there are unknowable necessities – an assumption we have no reason to grant, but that at least suggests the intuitive need for a non-epistemic foundation to modality.

Chapter Three set about exploring this idea further. I presented a metaphysically ‘realist’ understanding of metaphysical modality, and defended it against the conceptualist’s skepticism by highlighting its connection to our intuitive ideas about physical indeterminism, objective chance, and the open future. The realist’s primitive conception of modality forces us to take seriously the idea of strong necessities, but they need not give up on modal rationalism altogether. I suggest two principles of modal expansion – the presumption of possibility, and the consistency principle – which together serve to ground modal rationalism on a realist foundation. The end result is, I think, an attractive and defensible view, which preserves many of the intuitive claims we would wish to make about modality. And although it is arguably the conceptualist’s epistemic space that matters for key theoretical purposes, many would dispute this claim – which cannot be fully defended here – so it is worth establishing the viability of realist modal rationalism for those who would place greater weight on this metaphysical modal space.

Categories:

• essays
• metaphysics
• modality
• apriority
• semantics

Actuality and Counterfactuality

Suppose that, homicidal maniac that you are, you confess to me: "I would kill all my enemies if I thought I could get away with it." (I'll condense this to "SAFE []--> KILL ENEMIES".) What does this mean, exactly? Brit Brogaard suggests that the consequent is triply ambiguous. It could refer to your actual enemies, or to the enemies you would have if the antecedent (SAFE) were satisfied, or else to those of your actual enemies that would still exist were SAFE satisfied. (I may have picked a bad example, if the antecedent is itself similarly ambiguous, but we could replace it with, e.g., "if I could turn invisible...", to ensure that the same possible world w is invoked in all three analyses.)

None of these analyses seems entirely satisfactory, though. Suppose that the nearest possible world where you can turn invisible (or whatever) is also one where you became a pacifist. So, in that world w, you wouldn't kill anyone: not your local enemies, and certainly not your actual enemies (who may just as well be strangers or friends to you in w). Understood in possible-worlds terms, the counterfactual is then strictly false, no matter which way you interpret it. Still, it seems to me, the original confession need not be mistaken, if the only thing holding back your homicidal tendencies in the actual world is the fear of getting caught.

What happens in other possible worlds seems less relevant here. So what if it happens that the satisfaction of the SAFE condition would coincide with your becoming a pacifist? It doesn't change the fact that, as things stand, you're a dangerous maniac. (No offense, heh.) Your confession serves to relate your actual dispositions, rather than claiming anything about (potentially deviant) counterfactuals.

[I should note that Brandon and Chris offer some interesting discussion on related issues.]

But perhaps that's extra pragmatic information that we take away from the conversation, beyond its literal truth conditions. My intuitions are a bit vague here, but I guess there's some pull to concede that your assertion would be literally false in the scenario I've described. Perhaps the point is simply that it isn't meant to be understood literally.

Quick poll: what do you think are the truth conditions of the confession? What about its meaning?

Categories:

• semantics
• modality

Demonstratives and Apriority

Can non-trivial thoughts involving demonstratives ('this' or 'that') be a priori? (By "non-trivial", I mean that the truth of the thought depends on what is being demonstrated; not just any old target will do.) Chalmers' epistemic space framework suggests not, since it treats what's demonstrated as variable across centred worlds. That means that there will be some epistemically possible scenarios in which the target of my demonstration will be "any old thing", and hence my thought will come out false at that scenario, and hence it actually fails to be a priori.

But we might've expected the contrary result to be possible. Consider the following passage taken out of context from Laurence Bonjour's In Defense of Pure Reason (pp.57-58):

I am presently looking at two books on my desk. Both are darkish blue, but not quite the same shade of darkish blue, though my rather meagre color vocabulary contains no names for these specific shades nor any other way of indicating them linguistically. On this basis, I come to believe and, so far as I can see, to know a priori a certain proposition that I can only indicate indirectly but cannot adequately express in language, the proposition that nothing could be both of these colors all over at the same time...

(Bonjour uses this to show that a priori justification cannot be accounted for merely by "linguistic convention". My current purposes are completely different.)

Now, one way that I would be tempted to state the described a priori thought is as follows:

(D) Nothing could be that colour [mental nod towards first book] and that colour [mental nod towards second book] all over at the same time.

Is D a priori? It seems to depend on whether the demonstrated colours are themselves part of the tokened thought, or whether the demonstrations are mere placeholders. If the colours are "built in", then the resulting thought is certainly a priori. (Those two colours are themselves incompatible in all scenarios.) However, if the thought instead contains "placeholders", then it is not a priori, since this allows different targets to "fill the gap" in different scenarios. In particular, it allows a scenario in which we pick out the same colour twice. Such a scenario falsifies D, so understood, since things can of course be one and the same colour all over at the same time. Failing to be true at all scenarios, D thereby fails to be a priori.

As I understand it, Chalmers' framework requires that we adopt the second interpretation: demonstratives are variable placeholders, and so "non-trivial" demonstrative thoughts cannot be a priori. Is that a problem? Should we want to allow the first interpretation? We will at least want to allow some thought or other to have this "built in" content. But perhaps we should deny that those are "demonstrative thoughts" any longer. We might instead suggest that Bonjour was thinking something along the lines of:

(D*) "Nothing could be colour1 and colour2 all over at the same time." (Those "colour" labels might be replaced by appropriate items of direct phenomenology, say mental images of the colours in question. We want epistemically rigid designation, anyway, however that is done. The two colours should be held fixed across all scenarios.)

Note that there's nothing essentially "demonstrative" about D*. Lacking the vocabulary to express the thought directly, perhaps the best we could do verbally is to say something like D instead, and point to the two colours we have in mind. But really it is the two colours, and not the pointing, that we do in fact have in mind. So I think that provides some independent support for the claim that, contrary to my initial speculation, Bonjour's a priori thought is not a demonstrative one.

Is that the best way to make sense of this problem? (Is the answer to that question -- or this one -- a priori? Heh.)

Categories:

• apriority
• mind
• 2d
• semantics

Considering as Actual

Jessica Owensby-Sandifer (not to be confused with the other Sandefur!) offers an interesting argument against Chalmers' two-dimensionalism. It's a thoughtful piece which nicely (though unintentionally) illustrates the confusion which can arise from the standard picture of modal space.

The core problem, which Jessica recognizes, is that the standard picture leaves no room for the possibility of any other world being actual, "because for each universe there can be only one actual world." (I assume 'universe' here denotes modal space, or what I sometimes call the 'modalverse'.) She accepts this result and in response proposes a meta-modal space, i.e. a space of modalverses, so that each possible world can be actualized in a different modalverse. I guess this would mean that even though no other world can (in fact) possibly be actual, perhaps it's possible that this could have been possible. It's not true in any possible world of our modalverse. But it is true of another possible world in another possible modalverse. (I find such meta-modal claims deeply fascinating, but of dubious coherence.)

I think that's the wrong response, though. We should instead take the above 'narrow fatalism' to be a reductio of the standard picture. Jessica writes, "Central to the intuitive notions underlying a theory of actuality is the idea that something distinguishes the actual world from being a merely possible world." Indeed. I say that this concrete lump of ours isn't any kind of possible world at all ("merely" or otherwise!). If we think of possible worlds as being maximal properties, then our lump instantiates just one of those properties, which we might call the "actualized world-state". But the lump should not be identified with the property. It could have instantiated a different property, after all (whereas the first property has its identity essentially, and so could not have been the second property). In that case, a different possible world-state would have been actualized. And, intuitively, that's exactly what it means to say that another possible world could have been actual. It means that our concrete lump (*thumps table*) could have turned out a different way. It happens to instantiate world-property w1, but it could have had w2 instead. (Note that these are primitive extra-modal facts which cannot be spelled out using the standard "possible worlds" semantics.)

Now, Jessica wants to suggest a special problem for the two-dimensionalist's notion of "considering a world as actual". She writes:

It my contention that, no matter which theory of actuality one assumes, to consider another world as actual is to make a metamodal claim about the possibility that some other world is actual in another universe or cosmos.

But that can't be right. To consider a world as actual is to invoke the epistemic rather than subjunctive mode of possibility. To consider w2 as actual is to entertain the hypothesis that our lump (not some other one) actually instantiates w2. After all, this might really be the case for all we know a priori.

The lump/property distinction is crucial for making sense of this. For suppose all we could refer to as the 'actual world' is our world-property w1. Then to consider the distinct world w2 "as actual" would be to consider w2 as w1. But that's incoherent. Of course, that's not what anyone takes themselves to be doing when they consider worlds as actual. We're not considering one "world" or property to be another world/property. Rather, we're considering that world to be actual (*bangs table*), i.e. for the property to be actualized by the extra-modal lump.

A simple example might help clarify matters. Let w2 be the Twin Earth world, where XYZ fills the lakes and rivers. We can consider this world as actual, and come to the conclusion that 'water is XYZ' is 1-possible. This is because we're told that XYZ plays the water role in w2, and it's a priori that water actually plays the water role, and hence the indicative conditional "if w2 is actual then XYZ is water" is a priori. No problems.

Even if water is actually H2O, that doesn't mean we were entertaining the hypothesis that H2O is XYZ. That's not how epistemic possibility works: 'H2O' and 'water' are distinct concepts, even if they are actually the same substance. It certainly isn't a priori that "if w2 is actual then XYZ is H2O" -- indeed, that's a priori false! So we need to take care to distinguish the general notion of 'actuality' from the specific world-property which happens to be actualized.

(Another way to respond here would be to invoke the de dicto/de re distinction as it applies to the indexical analysis of 'actual'. For more on this, see my post: P iff actually P.)

Categories:

• 2d
• modality
• metaphysics

Godless Worlds

This Missouri post poses an interesting dilemma:

Suppose there’s a perfect God. If so, then he wouldn’t create any subpar worlds. For example, if there’s a world in which all creatures endure nothing but undeserved horrible suffering, then God wouldn’t create that world. But, since God exists in ALL possible worlds, it would be impossible for there to be a possible world such as I described because God would also exist and God’s existence would be incompatible with that world.

There clearly are sub-par possible worlds, or worlds which contain "gratuitous evil" (there's nothing incoherent about the concept). So I take this to show that God does not exist in all possible worlds.

Justin adds in comments:

This might get to the distinction between logical possibility and metaphysical possibility that I’ve heard folks in PR talk about (doesn’t Plantinga make the distinction?). It’s not logically impossible for gratuitous evil to exist, but it’s metaphysically impossible. Anybody else know much about how this distinction’s supposed to work? Would that solve the problem?

The distinction is explained in my post Misusing Kripke; Misdescribing Worlds. The present case would be a clear misapplication of the Kripkean semantic distinction, since we would require a different space of worlds, and not merely a different way of describing them. (See linked post for full explanation.)

But perhaps we could employ the more radical distinction that I've previously raised, i.e. the distinction between possible worlds generally (a content-based specification requiring mere coherence), and those that really could have been actualized (an irreducibly modal property).

[This may be what other philosophers have in mind with the conceptual/metaphysical possibility distinction. But that one is too often defended by a misguided appeal to Kripke/Putnam cases that merely support a semantic distinction. I will use a different terminology in order to clarify the difference, and distance myself from such misguided defences.]

A theist might think that there is an important sense in which God couldn't have failed to exist. But his non-existence isn't logically incoherent, so there is a "possible world" (in the standard sense of the term) representing this state of affairs. Now, if the only way for a possible world to be actualized is through God's acts of Creation,* then these possible worlds are ones that couldn't (really) possibly be actualized. (I assume the theist holds that God cannot cease to exist, and so cannot create a world in which He doesn't exist.) So it may be misleading to call them "possible worlds". However, that seems the standard practice of contemporary philosophers. So long as we keep clear on the different kinds of possibility we're talking about here, it hopefully won't cause too many problems.

Armed with my distinction, then, a theist can allow that a Godless world containing gratuitous evil is a coherent possibility, one that cannot be ruled out a priori even on ideal reflection and when described in semantically neutral terms (which rules out Kripkean a posteriori necessities). Nevertheless, they might hold God's existence to be what Chalmers calls a "strong necessity" (see sections 7-10 of the linked paper. Note that Chalmers argues against such a view).

* = [But why think that the only way for a possible world to be actualized is through God's acts of Creation? Perhaps a world could obtain through brute fact, as many atheists (myself tentatively included) believe is actually the case. It may be difficult to see why a world might obtain. But we could just as well ask: why not?]

Categories:

• modality
• metaphysics
• religion

P iff Actually P

Let '@' be the rigidifying 'actually' operator. "P iff @P" is a classic example of an a priori contingency. We can know a priori that P has the same truth value as it does in this world. But there are other possible worlds where its truth value differs from ours, and so "P iff @P" is false at such a world (recall, the extension of "@P" is always its truth value in our world), and hence merely contingent.

Now, Dave Chalmers [PDF] has used this to cleverly argue that no non-actual metaphysically possible world-state is also epistemically possible. The reductio (p.19):

Let W be one such world-state, and let P be a contingent statement that is true at @ but false at W. By the reasoning above, <P iff @P> is a priori, so true at all epistemically possible world-states, so true at W. It follows that @P is false at W.

But @P is a necessary truth, given that P is in fact true at @. So this contradicts our assumption that W is a metaphysically possible world. So, by reductio, there can be no such W that is non-actual, metaphysically possible, and also epistemically possible.

This highlights one way in which epistemic space behaves differently from metaphysical modal space. In particular, [where "true(P,W)" means "P is true at W"] the logical axiom:
(iv) ∀P ∀W (true(@P,W) ≡ true(P,@))
fails to hold for epistemic space. There are epistemically possible scenarios which represent the actual truth value of P to be other than what it truly is. This should be unsurprising when we recall that in epistemic modality we are considering each world as actual (rather than counterfactual). As such, rigid designation - as a feature of a term's secondary intension - gets ignored.

Still, one might think this a mere semantic trick. In epistemic modality we can't treat the term 'actual' rigidly; but surely we can stipulatively introduce another term to play the crucial role. This will have to involve super-rigidity, i.e. terms whose primary and secondary intensions are both invariant. We might take 'S' as our new super-rigid operator, and say that 'Sp' is the claim that p is true of some super-rigidly designated scenario S. Even if other epistemically possible scenarios deny that S is actual, surely none would wish to misdescribe the intrinsic content of S. So we should accept the modified principle, even for epistemic space:
(iv*) ∀p ∀W (true(Sp,W) ≡ true(p,S))

But can't we now super-rigidly designate the scenario which corresponds to actuality? Can't we demonstratively identify S as this (de re, rigidly designated), actual, scenario? And if so, can't we know a priori that "p iff Sp"? This would then provide a counterexample to the core thesis of epistemic two-dimensionalism, i.e. that Q is a priori iff Q is true in all epistemically possible scenarios (≡ Q has a necessary primary intension). For "p iff Sp" will be false in those non-actual scenarios W where the truth-value of p differs from its truth-value in scenario S.

Update: on second thought, the above clearly won't work, since what gets demonstrated will vary depending on which scenario we consider as actual. Demonstratives can't base super-rigidity, in other words. The best you can get from them is standard (secondary) rigidity, which doesn't apply to epistemic space, as already explained. I'll leave in my alternative response below, albeit bracketed, but I think I must have mistraced the background to the Soames-Chalmers dialectic.

[[ Scott Soames puts the proposal as follows [PDF, p.14]:

[A]gents in @, but not those in other world-states, can move apriori from any truth p in @ to the proposition that p is true in @, and vice versa, simply by identifying @ demonstratively, as “this very state that actually obtains.”

However, as Chalmers notes in his response to Soames, once we recognize that the actual world is not a possible world, it's no longer so clear that scenario S is ostendible after all. We can point to the actual world itself, of course. But we can't directly point to the scenario or possible world which accurately represents actuality. So we cannot know a priori that "p iff Sp"; not for any scenario S. (Without ostensive identification, S might could be a non-actual scenario, for all we know.) ]]

Let's conclude by contrasting three different interpretations of "P iff actually P".

1) No rigidity: here we use the term 'actually' as a fluid indexical, so that "P iff actually P" is logically equivalent to "P iff P" and hence both necessary and a priori. No problems here.

2) Subjunctive rigidity (the standard view): here we use the term 'actual' as a rigid designator, whose secondary intension is invariant, but the primary intension varies as in (1) above. This is the sense in which "P iff actually P" is contingent a priori. Note that it is true in all epistemically possible scenarios still. No problem for 2D-ism here.

3) Super-rigidity. There's not really any sense in which "actually" is super-rigid, but suppose we were to instead substitute the super-rigid specification of the scenario S (where S happens to be actual). Then "P iff in S, P" is not even a priori. Like any other old contingent a posteriori truth, it poses no problems either.

Categories:

• 2d
• semantics
• modality

Limited Omniscience

I think I've come up with a simpler way to characterize Chalmers' two-dimensionalism. A core idea is modal rationalism: the contents of possible worlds are a priori knowable (on ideal rational reflection). The only thing the ideal agent doesn't know a priori is which world is hers. Her only fundamental lack is this self-locating knowledge; from that, she could know all. (It's like a multiversal version of Lewis' Two Gods.)

The ideal agent can know all world-indexed qualitative facts, i.e. facts of the form "P is true at w", given in a semantically neutral "qualitative" language. That is, expressions must have identical primary and secondary intensions. Intuitively: descriptions good, rigid designators bad! The idea is to ensure that one can know the full meaning of the terms without needing to know which world is actual. Thus "watery stuff" is okay, but "water" is not. We can know that the former picks out both H2O and XYZ, without needing to know whether we live on Earth or Twin Earth. The term 'water', by contrast, requires this empirical knowledge in order to determine which of H2O or XYZ it rigidly designates.

Okay, so our semi-omniscient being knows pretty much everything except for what world she's in (and hence what rigid designators like 'water' refer to). And she knows all this a priori. So all a posteriori sentences must in some sense depend on one's location in modal space. They depend on which world is 'actual' (in the indexical sense, i.e. which world is ours).

We can now clearly see the problem diagnosed in my post Misusing Kripke; Misdescribing Worlds, i.e. why a posteriori necessities are generally uninteresting. Our ideal agent can see all the possible worlds, she knows just what they're like, in qualitative terms. So she knows what is "necessary" in any interesting sense. She just doesn't know how to describe it using rigidly designating terms. (You might think of her as a practising Descriptivist!)

Moreover, this ideal agent would surely know any ethical truths there are to know. (She doesn't need to know which world she's in for this. Her location is quite irrelevant to the question of whether some particular action was wrong.) And this conclusively refutes Synthetic Ethical Naturalism (or any other a posteriori meta-ethic).

Categories:

• 2d
• modality
• epistemology

Against Synthetic Ethical Naturalism

The synthetic ethical naturalist holds that there is an a posteriori identity between various moral and natural properties, much like that which holds between table salt and NaCl. I used to think this analogy sufficed to refute Moore's open question argument, but insights from two-dimensionalism shed doubt on this.

Misusing Kripke; Misdescribing Worlds

Too often, philosophers (including my past self) misunderstand Kripke as having shown that the space of metaphysically possible worlds does not include all logically/conceptually possible worlds. This leads to sloppy defences of physicalism. We may fail to take seriously the challenge of logically possible zombie worlds, prefering to dismiss them with a wave of the hand and some vague muttering about Kripke's necessary a posteriori. Or consider my own past sloppy defence of ethical naturalism, where I dismissed Moore's open question argument on the basis of an analogy with 'salt = NaCl'. Such swift dismissals are unwarranted -- let me now explain why.

The crucial point arose in my introduction to two-dimensionalism. The 2-D framework shows us that we need only one space of possible worlds, and the difference between 'conceptual' and 'metaphysical' necessity is merely a matter of how we consider the worlds in question (i.e. as actual, or as counterfactual). The point is made nicely by Frank Jackson in his From Metaphysics to Ethics, pp.77-78:

What convinced us [that 'water = H2O' is necessarily true, albeit a posteriori] were the arguments of Kripke and Putnam about how to describe certain possibilities, rather than arguments about what is possible per se. They convinced us that a world where XYZ is the watery stuff of our acquaintance did not warrant the description 'world where water is XYZ', and the stuff correctly described as water in a counterfactual world is the stuff - H2O - which is the watery stuff of our acquaintance in the actual world be it watery or not in the counterfactual world.

The key point is that the right way to describe a counterfactual world sometimes depends in part on how the actual world is, and not solely on how the counterfactual world is in itself. The point is not one about the space of possible worlds in some newly recognized sense of 'possible', but instead one about the role of the actual world in determining the correct way to describe certain counterfactual possible worlds.

So the Kripke/Putnam cases do not really shrink the space of possibilities. Nobody thinks that the 'Twin Earth' world Putnam describes is an impossible one. Rather, we still grant the possibility of the world itself, but merely re-assess how best to describe it. The necessity of 'water = H2O' says less about the space of possibilities than it does about our use of the term 'water'. All the same worlds are possible as before; it's just that now we refuse to use our term 'water' to describe any of the non-H2O stuff in any of those worlds.

It should now be obvious why appeals to the Kripkean necessary a posteriori do nothing to answer the aforementioned challenges. Consider the zombie world. We are conceiving of a genuine possible world, just as in the 'Twin Earth' case. The only question is how best to describe it. Perhaps our term 'consciousness' is, like 'water', a rigid designator. But who cares about the words? Twin Earth still contains watery stuff, even if we refuse to call it 'water', and the Zombie World still lacks phenomenal stuff (qualia), even if we stipulate that our term 'consciousness' refers to some neurophysical property (and so is guaranteed to exist in this physically identical world). Redescribing the Zombie world won't make the physicalist's problems go away. There's no denying that the world itself is possible, physically identical to our own, and yet lacking something of a mentalistic sort, however we end up describing it. And that's enough to refute physicalism (excepting Russellian monism, which allows us to deny that the zombie world is physically identical to our own).

We can clarify the point by appeal to the apparatus of 2-D semantics. Kripkean sentences which are necessary a posteriori have contingent primary intensions but necessary secondary intensions. But this cannot be the case for truths about consciousness, for our qualitative concepts are 'semantically neutral' in the sense that their primary and secondary intensions coincide.

Kripke himself noticed something along these lines. While we can imagine a world where watery stuff isn't truly water, it's incoherent to imagine a world where "painy" stuff isn't truly pain. To feel painful is to be painful. Whether something counts as 'conscious' does not depend on features of the actual world. We should come to the same judgments about consciousness regardless of whether we consider a world 'as actual' or 'as counterfactual'.

See also Dave Chalmers on 'The Two-Dimensional Argument Against Materialism'.

Categories:

• 2d
• modality
• metaphysics
• semantics
• mind
• consciousness
• philosophy

2-D Semantics

Words have meanings. But what does this involve? We can clarify matters by associating linguistic expressions with various "semantic values". The simplest one is perhaps extension, or what is actually 'picked out' by an expression. (N.B. 'Extension' is a technical term which is closely tied to our more intuitive notion of reference. The main difference is that we stipulate the extension of a sentence to be its truth value, but it would be strange to say that this is what the sentence refers to.) For example, "the U.S. president" and "George W. Bush" both refer to GWB. That flesh and blood object in the world is the extension of both terms. In general, the truth value of a sentence will be determined by the extensions of its component parts.

However, extension cannot be all there is to meaning. For one thing, not all true sentences mean the same thing! And even co-referential terms like those discussed above might come apart when we consider other possible worlds. Let W be a possible world where Kerry won the last U.S. election. Then "the U.S. President" picks out Kerry in world W, but "George W. Bush" certainly doesn't! This suggests a new semantic value, called an intension, which is a function from possible worlds to extensions. (That is, it associates an extension with each possible world.)

Recall that rigid designators (such as names) refer to the same object in all possible worlds. That is to say that they have a constant intension. The intension of 'George W. Bush' is GWB at all possible worlds. But the intension of 'the U.S. President' varies across worlds -- for any given world, it picks out whoever is the U.S. President in that world.

Since the extension of a sentence is its truth value, the intension of a sentence is a function from possible worlds to truth values. The intension of a sentence S tells us the truth value of S at each possible world. But recall that there are two ways we can interpret this. Philosophers since Kripke have standardly employed the subjunctive version, i.e. considering, for each world W, whether S would have been the case if W had been. This yields what Chalmers calls the secondary intension of S. (This is what most philosophers mean when speaking of an "intension", simpliciter.) But we can also appeal to the epistemic/indicative version, where we consider, for each world W, whether S is the case if W is. This yields the primary intension of S.

Note that the two intensions can come apart. For instance, 'water is H2O' has a necessary secondary intension: it is true in all possible worlds considered counterfactually. But the primary intension is merely contingent: it returns TRUE for our world, but FALSE for some others. For example, if we consider as actual a Twin Earth world where our lakes and rivers are filled with XYZ, then we should conclude that water is XYZ, not H2O.

It follows trivially from the definitions that a sentence S is metaphysically necessary iff it has a necessary secondary intension. What's more interesting to note is that S is a priori iff it has a necessary primary intension. After all, the only way we could know something without appeal to experience would be if that sentence is guaranteed to be true no matter which world turns out to be actual. That is, no matter which world we consider to be actual, we see that S is true. That is, S has a necessary primary intension. (And conversely: if it has a necessary primary intension, we can see it will be true no matter which world we consider as actual, so we can know it without appeal to experience.)

This sheds a lot of light on Kripkean cases of the contingent a priori, and the necessary a posteriori. Such cases arise when only one of the sentence's two intensions are necessary, as we saw in the 'water is H2O' example above.

Note that our grasp of primary intensions is a priori. This follows from Chalmers' thesis about the scrutability of truth. We can (given the idealization of perfect rationality) determine the truth value of any of our sentences if given enough information about how the world is. More generally, for any sufficiently complete hypothesis W about how the world is, we can determine whether S is true under that hypothesis -- and we can do this regardless of how the world actually happens to be. So we can know a priori a whole raft of conditional statements of the form 'if W then S'. We just can't know which world W is actual (i.e. which world-hypothesis is true) -- that requires empirical investigation.

Primary intensions thus provide a sort of "narrow content", or that component of meaning which is "all in the head". Its internal accessibility also allows it to play a role close to that of Fregean 'sense' (that broad notion of 'meaning' as tied to cognitive significance). Limitations arise in case of a priori sentences, which all share the same ("necessary") primary intension, despite differing in cognitive significance. More elaborate constructions might overcome this, but I will put the issue aside for now. My main purpose here is not to get into philosophy of language for its own sake, but rather to introduce the 2-D analytical tools that can help us in other areas of philosophy.

[Terminological note: primary intensions are sometimes also called '1-intensions', 'epistemic intensions', or 'A-intensions' (where "A" is for "Actual"). Secondary intensions are sometimes called '2-intensions', 'C-intensions' ("C" for "Counterfactual"), or just plain 'intensions', simpliciter.]

For more detail, see Dave Chalmers' introduction, 'Two Dimensional Semantics'.

Categories:

• 2d
• semantics
• modality

Intro to Two Dimensionalism

There are two ways we can conceive of other possible worlds. We can hold the actual world fixed and consider another world as counterfactual, which corresponds to the familiar notion of 'subjunctive', 'secondary', or 'metaphysical' possibility. Alternatively, we can consider a world as actual, which leads to the comparatively neglected notion of 'indicative', 'primary', 'conceptual', or 'deep epistemic'* possibility.

To elaborate: S is necessary if and only if S is true in all possible worlds. But we have these two ways of assessing the truth of S at each world W. We can take either the subjunctive reading - "If W had been the case, S would have been the case" - or else the indicative reading: "If W is the case, S is the case." If the former holds for all worlds W, then S is subjunctively necessary. If the latter holds for all worlds W, then S is indicatively necessary. But these two types of necessity can diverge.

For example, consider a world W where the clear drinkable liquid in lakes and rivers is XYZ rather than H2O. Considered counterfactually, we would describe this as a world without water. After all, water just is H2O (given the assumption that this identity holds in the actual world). This identity is "metaphysically necessary" - there is no possible world, considered counterfactually, where the identity is broken.

But let us instead consider world W as actual. If we accept the hypothesis that the clear drinkable liquid in our actual lakes and rivers is XYZ rather than H2O, then we rationally should conclude that water is XYZ, not H2O. So given that W is a possible world, a "way the world might be", there seems a straightforward sense in which it is possible for water to not be H2O. It is indicatively, but not subjunctively, possible.

We combine the two dimensions by assessing subjunctive possibility relative to a presupposed indicative possibility. For example, given the hypothesis that actually water is XYZ, it follows that a world with H2O in place of XYZ would be a world without water. After all, identities hold of subjunctive necessity. As Kripke's Naming and Necessity taught us, whether cats are animals or demons is a matter for empirical discovery -- but whichever they turn out to be, they are that essentially. If some other entity were of a different nature to our actual cats (whatever that nature might be), then it would not be a cat. A key insight of two-dimensionalism is to turn this presupposed 'actuality' into a variable that can itself range over various possible worlds. (To reiterate: this forms the 'indicative' sense of possibility, i.e. possible worlds considered as actual.)

Importantly, this sense of indicative or "conceptual" possibility is no mere pseudo-possibility. Indeed, it doesn't invoke a distinct modal space at all. On this explication of the 2-D framework, we do not contrast "metaphysically possible worlds" and "conceptually possible worlds". Rather, there's just one space of possible worlds, and the difference between 'metaphysical' and 'conceptual' possibilities merely lies in how we describe the worlds. (As already explained, we will describe them differently depending on whether we consider them as actual or counterfactual.) The full importance of this point will be brought out in subsequent posts, applying the 2-D framework to illuminate foundational issues in the philosophy of mind and meta-ethics.

I've hinted at the centrality of semantical considerations to the 2-D framework. My next post will spell this out more clearly by delving into some philosophy of language.

* = [Note that 'deep epistemic' possibility shouldn't be confused with the more superficial notion according to which anything we don't know to be false counts as "epistemically possible". Suppose a young math student doesn't yet know that there is no greatest prime number. Then the existence of such a number is an "epistemic possibility" for him, in the weak sense. Further, if we factor in experiential knowledge, then the claim that "I exist" is arguably "epistemically necessary" in the strict sense. But neither of these judgments hold true of indicative modality. There are possible worlds, considered as actual, where I do not exist. (Any uncentered world will do.) But there are none containing a greatest prime number. As these cases illustrate, Chalmers' notion of "deep" epistemic necessity abstracts away from a subject's actual knowledge and contingent cognitive limitations. It instead concerns what is a priori knowable on ideal rational reflection. On some views, this could depart from 'indicative necessity' as defined in this post. But I will save such complications for another day.]

Categories:

• 2d
• semantics
• modality
• metaphysics
• philosophy

Knowing Sentences

J.L. Dowell, in her Meaning, Reason, and Modality, raises an objection to Chalmers' 2-D semantics. Chalmers defines the apriority (hence 1-necessity) of a sentence-token in terms of the apriority of the thought it expresses. But Dowell points out that we cannot know a priori what the associated thought of a given sentence is. So 1-necessary sentences won't themselves be a priori knowable, thus (allegedly) breaking the link between meaning and reason which Chalmers wants for his "golden triangle".

Dowell writes:

To help focus the issue, consider first a clear case of a sentence-token’s being a priori, but not a priori knowable in the above senses. Suppose that Leverrier writes in his diary

(N) “Neptune is the planet, if any, that perturbs the orbit of Uranus”.

Let us suppose further that Leverrier has introduced “Neptune” into his idiolect as a name for whichever planet, if any, perturbs the orbit of Uranus. Given this, the thought expressed by N is both a priori and has a necessary epistemic intension (since it expresses the thought that the planet, if any, that perturbs the orbit of Uranus is the planet, if any, that perturbs the orbit from Uranus).

However, Dowell continues, anyone reading the diary has no way to know a priori, i.e. without experiential justification, what thought (N) expresses. (Indeed, she doesn't say it, but presumably we cannot even know what language it's written in. For all anyone knows a priori, the squiggles might have landed on the page through a massive coincidence of spilt ink, and so not mean anything at all.) So although (N) is a priori in Chalmers' thought-derived sense, the sentence itself is not a priori knowable. Someone presented with the sentence could not determine a priori whether it was true; first they would need to know what it means.

Dowell then argues:

[I]t is unclear how the a priority of sentence-tokens in Chalmers’ sense is a rational notion at all, given that it is divorced from what is a priori knowable and not characterized in terms of rational accessibility to agents, even idealized ones.

But this is silly -- Dowell is asking the impossible. On (my understanding of) her characterization of what it would take to know a sentence a priori, there are no a priori knowable sentences. So Chalmers' conception of sentence apriority is divorced from ["what is a priori knowable", namely:] nothing at all!

The core issue here concerns what sort of link we could hope to establish between reason and meaning. Dowell begins with the question of whether the 2-D framework can "ground an a priori-accessible, extension-fixing component of content for very many of our terms and sentences." But to ask that reason alone tell us the meaning of squiggles is certainly too demanding. It would be ludicrous to hold that sentence apriority is a matter of being able, when presented with some squiggles, to determine by reason alone whether the claim made by the squiggles is true.

No, we should be satisfied to make more modest demands on reason. A more reasonable challenge is to ask whether there is a component of content that is constitutively tied to apriority in the sense that Chalmers describes. Dowell complains that "this interpretation presupposes rather than grounds an a priori available component of content." But that only seems an objection if we misunderstand the aim of the framework. If what it takes for a component of content to be "a priori available" is for an agent to be able to determine the content of squiggles by reason alone, then (obviously!) no-one can provide such a thing, and nobody is trying to.

It might help here to invoke the distinction between semantics and meta-semantics. Whereas first-order semantics concerns the meaning of expressions, meta-semantics asks about how words get assigned their meanings to begin with (cf. the problem of intentionality). Now, Dowell is effectively demanding an a priori method for answering metasemantic questions (e.g. does some token of 'tiger' mean to talk about big cats or sofas?). But that's a ridiculous demand. We can all agree that such meta-semantic determination is an empirical matter. (Dowell calls this "the incontrovertible point".)

No, the only reasonable question to ask here is the first-order semantical one. Given that the words 'tiger' and 'sofa' actually have such-and-such semantic content (in particular, their respective primary intensions), can we determine whether "tigers are sofas" is a priori false, just in virtue of the meaning of the terms? Plausibly, we can. Perhaps a tiger carcass could be used in sofa manufacture, but I can't imagine any scenario in which it would turn out that tigers just are sofas. (Again, don't confuse this with the meta-semantic issue of whether we can imagine scenarios where the word 'tiger' would turn out to mean something completely different.)

Another way to put the point is to insist that our idealized agent be granted full command of the language in question. Perhaps Dowell intended to allow agents a coarse-grained version of the language, such as that which is shared by all competent English speakers. That would suffice to allow us to identify sentences like "Hesperus is Hesperus" as a priori, but not speaker-relative apriorities such as that expressed by (N). The problem with this is that it excludes a key component of meaning (according to the 2-D framework), namely, the 1-intension. Chalmers is explicit that 1-intensions are speaker-relative (hence the need to speak of sentence tokens rather than types), so the appropriate "language" will need to be fine-grained enough to accommodate this. In other words, the agent needs to be given the idiolect of the speaker.

Then the relevant question becomes whether an idealized agent who reads (N) in Leverrier's idiolect could, through a priori reasoning alone, come to know that (N) is true. And the answer is surely 'yes'. A perfectly competent speaker of Leverrier's idiolect will grasp the primary intension of 'Neptune' so used, and thus recognize the thought expressed by (N) as being 1-necessary and hence knowable a priori. This seems to be "an interpretation that genuinely links reason [and] meaning... in a substantive way." Of course if we strip a sentence of its meaning, then our rational notions can get no grip on it. But that does nothing to cast doubt on Chalmers' links between meaning, reason, and modality. The claim isn't that reason can magically discern the meaning of squiggles. Rather, it is that reason can determine whether, given the meaning of a sentence, it must be true. This establishes substantive connections between the semantic notion of a primary intension, the rational notion of apriority, and the modal notion of 1-necessity.

Categories:

• 2d
• semantics
• epistemology

Counterfactual Commitments

There was some interesting discussion over at Think Tonk recently. Clayton was arguing that theists can't fault Evolutionary Naturalism on the basis (advanced by Plantinga) that our rational faculties would be unreliable if EN were true. After all, such theists think we actually do have reliable faculties, and so if evolution created us just the way we are, then we would have the exact same (equally reliable) faculties. It's a neat - if flawed - argument, and provides a good opportunity to explore some modal issues that I'm interested in.

A key aspect of my response was to highlight two different ways of thinking about alternative possibilities. One is to treat them as standard counterfactuals, which involve presuppositions about what is actually the case. (For example, our judgment that if there was no H2O then there would be no water is based on the presupposition that the watery stuff of our actual acquaintence is H2O.) But there is another way to go, which is to conceive of the alternative as actual. (Call this conception "counter-actual".) For example, we might speculate about whether, perhaps, chemists are mistaken and water is actually composed of some other XYZ. Clearly our affirmation of the earlier counterfactual does not commit us to the absurd claim that if there is actually no H2O (because our watery stuff is really XYZ) then there is no water. Counterfactuals do not commit us to the corresponding counter-actuals.

This has important consequences for Plantinga's argument. Given the assumption that God created us with reliable faculties, the theist can't very well deny the counterfactual that if creatures evolved naturally to be just like we are, then they too would have reliable faculties. They must concede this much. But this doesn't entail the corresponding counter-actual. Plantinga can still consistently assert that if we actually evolved naturally, then we probably don't have reliable faculties. (I would dispute that claim, of course, but my point is simply that it is consistent with the aforementioned counterfactual.)

One way to understand this dialectic is to contrast the epistemic and metaphysical bases for the reliability of our faculties. Clayton points out that the reliability of our faculties supervenes on our constitution, and not its origins. So if we fix the constitution facts and let only the origins change, the 'reliability' facts will remain fixed. This is reflected in the counterfactual judgment.

However, suppose that our only reason for believing our faculties to be reliable is that we think God created us. Here it is facts about our origin, and not our constitution, that provide the epistemic basis for thinking our faculties to be reliable. So if we fix the constitution facts and let the origins change, then our beliefs about the 'reliability' facts should change. This is reflected in the counter-actual judgment.

These different judgments arise because counterfactuals map out a metaphysical modal space, whereas counter-actuals can instead be used to map out a sort of epistemic modal space.

I just thought that was an interesting point to clarify.

(Disclaimer: views and arguments attributed to 'Clayton' are presented here for dialectical purposes, and might not reflect Clayton's actual views. Readers are encouraged to read his blog for that.)

Categories:

• modality
• metaphysics
• epistemology
• rationality
• naturalism
• philosophy

Actual Ambiguities

Consider the term: "the actual world". It means, transparently enough, something along the lines of "that possible world which is actual". As with many definite descriptions, this displays a sort of de dicto/de re ambiguity. On the one hand, we might take the term 'the actual world' as a straightforward description (or a kind of modal indexical), so that any possible world can refer to itself by using the term, if we conceive of that world as "counteractual" rather than merely counterfactual, i.e. when we conceive of that world as having been actualized in place of our own world. This is analogous to how the de dicto reading of "the U.S. president" allows it to refer to John Kerry in some possible worlds, even though Kerry isn't president in our world. Much like Kerry could have been president in place of Bush, so, perhaps, some other possible world could have been actual in place of our own. (I'm actually not convinced that's a meaningful suggestion. But I'll ignore such worries for now.)

Alternatively, we might take the term to be a sort of name or rigid designator, the description picking out an actual object, but thereafter holding the reference fixed throughout all possible worlds. So, for example, if we rigidly designate X = "the [actual] U.S. president", then 'X' is just another name for George W. Bush, and in counterfactual worlds where Kerry is president, it would be false to say "X is the U.S. President", because Bush wouldn't be. Applying this to our present problem, we might take "the actual world" to be a name rigidly designating our own particular world. On this reading, if my counterpart on a frozen possible world were to say "I'm actually cold" (in the philosophical sense of "I'm cold in the actual world"), then he would be saying something false, since in the actual world - i.e. our one - I'm not cold. On the de dicto reading previously mentioned, however, he might well be saying something true. It would be true just in case he was cold, on his world.

Okay, hopefully that's all clear. Now, I bring this up because it's relevant to a couple of recent posts over at Fake Barn Country. In one, Jonathan argues that we cannot believe metaphysical contingencies, because a belief that p just is a belief that actually p, but the truth value of the latter belief's content is metaphysically necessary (if true, it's necessarily true; if false, it's necessarily false). But this argument equivocates between the two senses of 'actually' described above.

A belief that p is only equivalent to a belief that actually p in the de dicto sense, i.e. where 'actually p' just means 'p in this world (conceived as actual)', that is, just plain 'p'. And there's nothing metaphysically necessary about the truth value of that. The stronger version doesn't work, because my frozen counterpart believes he is cold (i.e. "RC is cold"), but he doesn't necessarily believe that I, his actualized counterpart, am cold. He doesn't know anything about my situation. His beliefs are about his possible world, not mine. And a belief about his world is clearly not the same as a belief about my world. So, these counterfactual people show that a belief that p is not the same as a belief that actually p -- not in the strong (de re) sense that Jonathan requires.

In an earlier post, Jonathan made the following claim:

"Claim: To imagine a scenario is to imagine that the scenario obtains in the actual world."

I suggested in comments that this is only true in the de dicto sense. A better way to put it might be that we imagine scenarios as counter-actual, rather than actual. We don't imagine them taking place in this very world [the de re actual world], where I'm warm and Bush is president. Rather, it seems to me, we imagine scenarios (fictions especially) as taking place in some other world, a world which we then conceive of as being actual in place of our world.

None of the FBC guys seemed especially taken by the idea, which is odd, because it strikes me as obviously correct. (Then again, Jonathan thought his claim was obviously true too, which I strongly disagree with, so perhaps 'obvious' is a dangerous word to be throwing around in this discussion!) What do you guys think?

Categories:

• philosophy
• metaphysics
• imagination
• semantics