...where [\phi]_classical is the conservative semanticist's (e.g. the Gricean's) analysis of sentence \phi, the free choice sentence isn't equivalent to anything of the `implicature-strengthened' form [\phi]_classical + p, except in the trivial case where p = the conclusion of the inference. NB that usually p = ~r, where r is some relevant stronger alternative to the proposition \phi expresses.
Examples of the pattern:
(1) A v B = [A v B]_classical + \neg(A & B)
("A & B" is a relevant alternative to "A v B" on the Horn-scale; obviously "A & B" is stronger than "A v B"_class)
(2) Three F G = [Three F G]_classical + \neg(more than three F G)
("n F G", for n greater than 3, are all relevant alternatives to "three F G" on the Horn-scale; each of these n would entail [three F G]_class, and hence are stronger relevant alternatives)
(3) Warm(a) = [Warm(a)]_classical + \neg[Hot(a)]_classical
(4) Mary likes SUE / Mary likes (only) Sue
= [Mary likes Sue]_classical + \forall x (x \neq Sue) -> neg(Mary likes x)
Possible response on behalf of (neo-)Gricean: maybe you could express the missing p = ~r if you used `only' in the specification of p?
(5?) Might(p v q) = [Might (p v q)]_classical + \neg(Might only p) ??
But that's very odd. In what sense is "Might only p" a relevant alternative to a part or whole of the original sentence? Plus, if you're allowed to use "only"s in the specification of the relevant alternatives, I could run disastrous symmetry arguments against the entire Neo-Gricean enterprise:
(6) A v B = [A v B]_classical + \neg(Only A) => A & B.
(!!!) Perhaps this is what Fox is working to avoid in his 2006 paper.
Tuesday, May 17, 2011
Monday, April 18, 2011
Defending against `contextualism'
I am discussing views on which experience presents (represents?...) certain colors. What about `contextualist' or `situation-dependent' views on which this is not true? Here is one such view from Sean Kelly:
``On my view the phenomenon of perceptual constancy shows us something crucial about the context dependence of perceptual experience. In particular, it shows us that the complete and accurate account of my perceptual experience of the color of an object must contain some reference to the lighting context in which that color is perceived. Without a reference to the context we won't have the resources necessary to explain the change in experience that occurs when the lighting context is varied. If this is right, as all perceptual psychologists agree, that this change in not a change in color (hence the name `color constancy'), then no color concept, not even a demonstrative one, could completely describe the content of a color experience...[the perceptual demonstrative] `that color' is unable to distinguish between that color as presented in the sun and the same color as presented in the shade. Because the relevant difference is not a difference in color, no color term could make such a distinction. Since such a distinction is clearly made in experience---the color looks different in the sun than in the shade---the demonstrative concept is inadequate to account for the experience." (Kelly, ``The non-conceptual content of perceptual experience," PPR May 2001, pg 607)
What exactly to make of this? Let us accept the view that one and the same color looks different in the sun than in the shade. When I carry the sample from sun to shade, my experience changes, but the represented color doesn't change. Conclusion: my experience represents both lighting and color. [Comparison: I am testing to see whether my friend can hold his breath for a minute. I watch him for a full minute while he is underwater. My experience represents that he hasn't moved, but clearly my experience has represented some kind of change: the passage of time---my experience represents both position and time.] What shall we say, then? One thing would be a temporalist-type view of content: my experience maps color-lighting ordered-pairs to truth-values. Another view would be more eternalist: my experience represents a color at a certain fixed lighting. The lighting, being a feature of context, need not be represented by me in any way; it's merely an external feature needed for the `completeness' of the truth-conditions associated with my experience. It seems like the guiding thought for deciding between these view might be: could I have had the exact same experience under different lighting? If yes, then it is fair to say that my experience only represents a function from ordered pairs of color-and-lighting to truth-values; if no, then a more temporalist view is suggested. Either way, it does seem like a simple instruction to `fix the lighting' would be ok.
...Well, I don't know. How is Kelly's argument about demonstratives supposed to work? The idea must be that a demonstrative term like ``that shade" picks out a function from colors to truth-values, while the content of experience must be a function from color-lighting pairs to truth-values. Does it then follow that ``no color concept, not even a demonstrative one, could completely describe the content of a color experience...[since the perceptual demonstrative] `that color' is unable to distinguish between that color as presented in the sun and the same color as presented in the shade"? I suppose so; what the referent of the demonstrative would contribute is a function from lighting-conditions to truth-values; but the content of perception fixes the lighting as well as the shade. Our experiences are `opinionated' w.r.t. the lighting conditions, but the content of the demonstrative ``that shade'' is not.
``On my view the phenomenon of perceptual constancy shows us something crucial about the context dependence of perceptual experience. In particular, it shows us that the complete and accurate account of my perceptual experience of the color of an object must contain some reference to the lighting context in which that color is perceived. Without a reference to the context we won't have the resources necessary to explain the change in experience that occurs when the lighting context is varied. If this is right, as all perceptual psychologists agree, that this change in not a change in color (hence the name `color constancy'), then no color concept, not even a demonstrative one, could completely describe the content of a color experience...[the perceptual demonstrative] `that color' is unable to distinguish between that color as presented in the sun and the same color as presented in the shade. Because the relevant difference is not a difference in color, no color term could make such a distinction. Since such a distinction is clearly made in experience---the color looks different in the sun than in the shade---the demonstrative concept is inadequate to account for the experience." (Kelly, ``The non-conceptual content of perceptual experience," PPR May 2001, pg 607)
What exactly to make of this? Let us accept the view that one and the same color looks different in the sun than in the shade. When I carry the sample from sun to shade, my experience changes, but the represented color doesn't change. Conclusion: my experience represents both lighting and color. [Comparison: I am testing to see whether my friend can hold his breath for a minute. I watch him for a full minute while he is underwater. My experience represents that he hasn't moved, but clearly my experience has represented some kind of change: the passage of time---my experience represents both position and time.] What shall we say, then? One thing would be a temporalist-type view of content: my experience maps color-lighting ordered-pairs to truth-values. Another view would be more eternalist: my experience represents a color at a certain fixed lighting. The lighting, being a feature of context, need not be represented by me in any way; it's merely an external feature needed for the `completeness' of the truth-conditions associated with my experience. It seems like the guiding thought for deciding between these view might be: could I have had the exact same experience under different lighting? If yes, then it is fair to say that my experience only represents a function from ordered pairs of color-and-lighting to truth-values; if no, then a more temporalist view is suggested. Either way, it does seem like a simple instruction to `fix the lighting' would be ok.
...Well, I don't know. How is Kelly's argument about demonstratives supposed to work? The idea must be that a demonstrative term like ``that shade" picks out a function from colors to truth-values, while the content of experience must be a function from color-lighting pairs to truth-values. Does it then follow that ``no color concept, not even a demonstrative one, could completely describe the content of a color experience...[since the perceptual demonstrative] `that color' is unable to distinguish between that color as presented in the sun and the same color as presented in the shade"? I suppose so; what the referent of the demonstrative would contribute is a function from lighting-conditions to truth-values; but the content of perception fixes the lighting as well as the shade. Our experiences are `opinionated' w.r.t. the lighting conditions, but the content of the demonstrative ``that shade'' is not.
Sunday, April 10, 2011
Sennet on Binding and ``Free Enrichment"
I discovered this article, ``The Binding Argument and Pragmatic Enrichment, or, why philosophers care even more than weathermen about `raining'" on Philpapers while searching for``Free Enrichment." I must regrettably say that I am still somewhat in the dark as to what ``Free Enrichment" means. But let us meditate on the article all the same.
Consider the simple fact that
(1) It's raining.
...uttered by John in Oxford at time t, is true iff it is raining *in Oxford* at t. Is there a hidden variable in (1)? I thought that the hidden variable at issue would be a variable for *times*. This would be sensical since we analyze
(2) It's always raining
as
(2') ALWAYS: it's raining
as
(2'') At : it rains at t.
i.e., we need a `t' in (1) so that we can bind it with the quantifier ``Always." [I hope this is right anyway...check email exchange with MacF...] But I was mistaken! We were actually considering (1) qua argument that there is a hidden variable l for *location* in (1), because intuitively (1), uttered in Oxford, is only true if it's raining in Oxford. Ok.
It gets weirder, though. It seems (from the expanded title and remarks at the end of the paper) that Sennet is considering the view that these considerations about (1) show that ``rains" is context-sensitive. WHOAH! That seems like weird view to motivate on (1). After all (1) has more than one word. *Which* constituent of the sentence that expresses p should we declare context-sensitive on the basis that p is true, uttered at l, iff p is true at l? This seems dangerously underdetermined. And bizarre.
Let's start again, putting context-sensitivity first, a la Cappelen and Lepore. Consider the dude who wishes to hold that ``tall" is context-sensitive, and that it can sometimes mean ``tall for a basketball player." Now I understand that there are two ways to make the claim. One is that there is an unarticulated constituent in the sentence
(3) Billy is tall
...on some occasion of use in which (3) intuitively means that he's tall for a basketball player. So the LF of (3) is really
(3') Billy is tall-for-x
where x is a variable for a comparison class. Now, when (3') is uttered unembedded, context saturates the value for x, giving us x_c, the comparison-class-of-the-context. So far, so good.
To one who protests that putting extra junk in (3) to get (3') is undermotivated, we urge that there are often hidden variables in sentences. Consider any garden-variety use of PRO:
(4) Mary wanted PRO to leave.
...Sennet will call an argument that (3') is the LF of (3), on analogy with (4), a view on which there are hidden semantic constituents. It is an example of *semantic enrichment,* not *pragmatic enrichment.* Pragmatic enrichment is a no-no, according to certain doctrines that take the semantics-pragmatics divide seriously. So we can see this argument that there is a hidden variable in LF for (1) and (3) as a CONSERVATIVE move against people who think there is pragmatic enrichment. The question seems to hinge on considerations like this: when you interpret (3) as meaning that Billy is tall for a basketball player, does your analysis go by way of settling some locations and values of some hidden variables, as it does when you disambiguate different readings of e.g. ``Every boy loves his mother"?
...It turns out that the consideration of (2) I advanced is called THE BINDING ARGUMENT, and it is controversial! The binding argument takes a sentence s and considers embedded versions of it, where the embedded s seems to be quantified into/over by the embedding quantifier. For example:
(1) It's raining.
(5) Everywhere Bianca goes, it's raining.
(2) It's always raining.
The binding argument seeks out embeddings of s that seem (semantically) ``dependent" on the embedding environment, i.e. as in (2) and (5). It then concludes that there is a hidden constituent---two actually!---available for binding in (1).
Sennet locates two assumptions on which the Binding Argument depends. The first he calls Semantic Innocence (SI). This says, roughly, that what looks like an embedded occurrence of s really is one--that embedded and unembedded occurrences have the same LF. The second is called the Binding Assumption (BA). I'm not sure what to make of it, except that it says that where binding occurs, it occurs(?): that detected semantic ``dependence" (i.e., semantic interaction) can be traced to binding.
We then consider rejections of the binding argument. I must say it is not at all clear what the broader dialectic is here: if we reject the binding argument, are we back to ``pragmatic enrichment" a la Perry for (1)? Surely not ?...
Anyway, attacks on the binding argument fall into several cases. We may deny SI and we may deny BA. Recanati, Sennet suggests, denies SI. This is just to say he holds that there might need to be invisible variables in embedded occurrences of s, but that doesn't mean that there are invisible variables in *unembedded occurrences* of s. Sennet is dismissive of this approach because a lot of dependent occurrences are dependent occurrences of individual words, not whole sentences. He invites us to consider (8):
(8) Every sports league supports the application of a tall player.
...there is no well-formed subsentential sentence in (8). But we still have the intuition that `tall' may well be context-sensitive in (8).
I feel that this point is a little inconclusive because it's completely unclear whether we're talking about the variable-sensitivity of sentence-truth to certain parameters, or the *context-sensitivity* of certain *words*!
The second way is to deny BA. How does one do this? Well, perhaps the kind of evidence we've considered isn't sufficient to show the presence of (hidden) variables. Two sorts of considerations: Partee's and Cappelen/Lepore's. Partee points out that hidden variables should be capable of felicitously being made explicit, and it's not clear this can be done:
(12?!) A man from every country hates a foreigner *to it.*
...this seems like a bad argument to me because, as has been pointed out by Ninan et al., ``John wants PRO to dance" is actually not semantically equivalent to ``John wants John to dance."
Another anti-binding consideration suggests that maybe the inference [to richer structure in the unembedded case, on considerations stemming from the embedded, bound-feeling cases] comes from the claim that ``variables have semantic values of their own." I guess this is just another way of denying that we have identical LFs in both cases: it's just that it isn't so weird to say that the variable's `gone missing' in one case and not the other if it's simply the case of a denotation-bearing lexical item that's failed to appear. Sennet quotes Stanley criticizing this move: while we can e.g. use ostension to make salient the referent of an explicit pronoun, can we do this in the case of a variable? It doesn't seem so. [I don't really understand this argument. You need ostension and salience for REFERENTIAL pronouns. You do not need them--can't have 'em, can you?--for BOUND pronouns.]
Another view would hold that pragmatic processes result in the insertion of a boundable (and bound) pronoun in the bound cases; this also allows us to keep variables out of unembedded cases. As Sennet puts it, `the dialogue gets murky here.' Is this semantic or pragmatic enrichment, or both? He also points out that if we could always posit hidden boundable (and bound) pronouns wherever we needed to to make a sentence grammatical, we should be able to hear
(15) Every woman likes house.
...as grammatical, by positing a covert ``her" (bound) between ``likes" and ``house." But we can't really do that. So it doesn't seem like that explains what's going on in ``it's always raining" or ``Wherever Bianca goes, it's raining."
One important comment to make here concerns Lewisian unselective quantifiers: while ``every'' is selective, plausibly, other quantifiers like ``it is rarely the case that..." or ``whenever..." are not. Indeed, we can see this with sentences like
(16) It is rarely the case that, wherever Bianca goes, it's raining.
The (possible) moral is that we *can* sometimes posit (type-unselective?) variables--variables for *cases*, perhaps--when a quantifier demands it, despite there being very little to be said for positing it in the unembedded case.
Anyway, the biggest objection to the binding argument is OVERGENERATION. This comes in two flavors: syntactic and semantic. For a purely syntactic one, consider the Cappelen and Lepore examples with `2+2=4':
(17) Wherever Bianca goes, 2+2=4.
(18) Whenever I step outside, 2+2=4.
etc...
(17) and (18) are not semantically dependent, in the sense that their truth-conditions presumably do not differ from the unembedded `2+2=4': no one is forced to hold that the truth-conditions of mathematical statements varies NON-VACUOUSLY with times and places. But perhaps to stuff the unembedded sentence with these hidden variables is unpalatable, even if they are truth-conditionally inert.
Sennet writes that the semantic version of the complaint of overgeneration is one about predicted, but unattested, context-sensitivity. We consider:
(19) John is anorexic, but whenever his father cooks mushrooms, he eats.
The idea is that (19) doesn't mean `...he eats THEM.'
I'm pretty bewildered by this. Why would it? That would have to be a hidden variable for a direct object--not a time, but a thing--which couldn't be quantified over by `whenever', anyway. The appropriate version of the sentence would be:
(20) John is anorexic, but *whatever* his father cooks [t], he eats [t].
...now that IS a genuinely bound reading! But...it has nothing to do with (19). This is absolutely puzzling. Perhaps the only point is that we should beware of what Sennet has loosely termed ``semantic dependence" or ``dependent readings." An intuition of dependence may be merely pragmatic, related to salience: the *suggestion*, but not the content, of (19) includes the proposition that John eats his father's mushrooms whenever his father cooks mushrooms.
We have reached the end of the article. I have to say I'm still not clear on the connection between two things: (i) context-dependence, and (ii) hidden variables. If some words, like `tall', are context-sensitive, perhaps there is a hidden variable in them saturated by context. Perhaps these variables can be bound. Perhaps, then, we can test for bound readings. But we don't have quantifiers that bind contrast classes, so...uh...maybe not. Worse, presumably people are claiming that `tall' works relatively like an INDEXICAL---MacFarlane's nonindexical contextualism being a rather exotic view (and going unmentioned by Sennet.) But if that's true, the context-sensitive items SHOULDN'T be bindable--any more than indexicals are! It's a dogma of Kaplanian semantics that there are no natural language binders or shifters of indexicals: these would be `monsters.'
To conclude: what is free enrichment? Well, minimally, it's the positing of a hidden variable at LF. Boring view: so there's really an unarticulated constituent at LF. Weird crazy view: there isn't one there...AT FIRST...but pragmatic processes `insert' it!! Uh...that's pretty weird, since presumably facts in the meat of the language-module of your brain don't depend on how I interpret your sentence by applying Gricean maxims. I take it that the real puzzle of (1)---though maybe I've just got the debate all wrong---is whether we want to take `metaphysical' considerations to put stuff in LF. I've suggested elsewhere that the way to consider that question is to consider a language where there are no temporal operators like `always:'. More broadly: whether we can freely insert things in LF so that sentences come out to have the truth-conditions we think they should, in some sense, `really' have...when are intuitions about what truth-conditions they REALLY have are obviously contaminated by the binders, etc. we have in our *own* language!
Consider the simple fact that
(1) It's raining.
...uttered by John in Oxford at time t, is true iff it is raining *in Oxford* at t. Is there a hidden variable in (1)? I thought that the hidden variable at issue would be a variable for *times*. This would be sensical since we analyze
(2) It's always raining
as
(2') ALWAYS: it's raining
as
(2'') At : it rains at t.
i.e., we need a `t' in (1) so that we can bind it with the quantifier ``Always." [I hope this is right anyway...check email exchange with MacF...] But I was mistaken! We were actually considering (1) qua argument that there is a hidden variable l for *location* in (1), because intuitively (1), uttered in Oxford, is only true if it's raining in Oxford. Ok.
It gets weirder, though. It seems (from the expanded title and remarks at the end of the paper) that Sennet is considering the view that these considerations about (1) show that ``rains" is context-sensitive. WHOAH! That seems like weird view to motivate on (1). After all (1) has more than one word. *Which* constituent of the sentence that expresses p should we declare context-sensitive on the basis that p is true, uttered at l, iff p is true at l? This seems dangerously underdetermined. And bizarre.
Let's start again, putting context-sensitivity first, a la Cappelen and Lepore. Consider the dude who wishes to hold that ``tall" is context-sensitive, and that it can sometimes mean ``tall for a basketball player." Now I understand that there are two ways to make the claim. One is that there is an unarticulated constituent in the sentence
(3) Billy is tall
...on some occasion of use in which (3) intuitively means that he's tall for a basketball player. So the LF of (3) is really
(3') Billy is tall-for-x
where x is a variable for a comparison class. Now, when (3') is uttered unembedded, context saturates the value for x, giving us x_c, the comparison-class-of-the-context. So far, so good.
To one who protests that putting extra junk in (3) to get (3') is undermotivated, we urge that there are often hidden variables in sentences. Consider any garden-variety use of PRO:
(4) Mary wanted PRO to leave.
...Sennet will call an argument that (3') is the LF of (3), on analogy with (4), a view on which there are hidden semantic constituents. It is an example of *semantic enrichment,* not *pragmatic enrichment.* Pragmatic enrichment is a no-no, according to certain doctrines that take the semantics-pragmatics divide seriously. So we can see this argument that there is a hidden variable in LF for (1) and (3) as a CONSERVATIVE move against people who think there is pragmatic enrichment. The question seems to hinge on considerations like this: when you interpret (3) as meaning that Billy is tall for a basketball player, does your analysis go by way of settling some locations and values of some hidden variables, as it does when you disambiguate different readings of e.g. ``Every boy loves his mother"?
...It turns out that the consideration of (2) I advanced is called THE BINDING ARGUMENT, and it is controversial! The binding argument takes a sentence s and considers embedded versions of it, where the embedded s seems to be quantified into/over by the embedding quantifier. For example:
(1) It's raining.
(5) Everywhere Bianca goes, it's raining.
(2) It's always raining.
The binding argument seeks out embeddings of s that seem (semantically) ``dependent" on the embedding environment, i.e. as in (2) and (5). It then concludes that there is a hidden constituent---two actually!---available for binding in (1).
Sennet locates two assumptions on which the Binding Argument depends. The first he calls Semantic Innocence (SI). This says, roughly, that what looks like an embedded occurrence of s really is one--that embedded and unembedded occurrences have the same LF. The second is called the Binding Assumption (BA). I'm not sure what to make of it, except that it says that where binding occurs, it occurs(?): that detected semantic ``dependence" (i.e., semantic interaction) can be traced to binding.
We then consider rejections of the binding argument. I must say it is not at all clear what the broader dialectic is here: if we reject the binding argument, are we back to ``pragmatic enrichment" a la Perry for (1)? Surely not ?...
Anyway, attacks on the binding argument fall into several cases. We may deny SI and we may deny BA. Recanati, Sennet suggests, denies SI. This is just to say he holds that there might need to be invisible variables in embedded occurrences of s, but that doesn't mean that there are invisible variables in *unembedded occurrences* of s. Sennet is dismissive of this approach because a lot of dependent occurrences are dependent occurrences of individual words, not whole sentences. He invites us to consider (8):
(8) Every sports league supports the application of a tall player.
...there is no well-formed subsentential sentence in (8). But we still have the intuition that `tall' may well be context-sensitive in (8).
I feel that this point is a little inconclusive because it's completely unclear whether we're talking about the variable-sensitivity of sentence-truth to certain parameters, or the *context-sensitivity* of certain *words*!
The second way is to deny BA. How does one do this? Well, perhaps the kind of evidence we've considered isn't sufficient to show the presence of (hidden) variables. Two sorts of considerations: Partee's and Cappelen/Lepore's. Partee points out that hidden variables should be capable of felicitously being made explicit, and it's not clear this can be done:
(12?!) A man from every country hates a foreigner *to it.*
...this seems like a bad argument to me because, as has been pointed out by Ninan et al., ``John wants PRO to dance" is actually not semantically equivalent to ``John wants John to dance."
Another anti-binding consideration suggests that maybe the inference [to richer structure in the unembedded case, on considerations stemming from the embedded, bound-feeling cases] comes from the claim that ``variables have semantic values of their own." I guess this is just another way of denying that we have identical LFs in both cases: it's just that it isn't so weird to say that the variable's `gone missing' in one case and not the other if it's simply the case of a denotation-bearing lexical item that's failed to appear. Sennet quotes Stanley criticizing this move: while we can e.g. use ostension to make salient the referent of an explicit pronoun, can we do this in the case of a variable? It doesn't seem so. [I don't really understand this argument. You need ostension and salience for REFERENTIAL pronouns. You do not need them--can't have 'em, can you?--for BOUND pronouns.]
Another view would hold that pragmatic processes result in the insertion of a boundable (and bound) pronoun in the bound cases; this also allows us to keep variables out of unembedded cases. As Sennet puts it, `the dialogue gets murky here.' Is this semantic or pragmatic enrichment, or both? He also points out that if we could always posit hidden boundable (and bound) pronouns wherever we needed to to make a sentence grammatical, we should be able to hear
(15) Every woman likes house.
...as grammatical, by positing a covert ``her" (bound) between ``likes" and ``house." But we can't really do that. So it doesn't seem like that explains what's going on in ``it's always raining" or ``Wherever Bianca goes, it's raining."
One important comment to make here concerns Lewisian unselective quantifiers: while ``every'' is selective, plausibly, other quantifiers like ``it is rarely the case that..." or ``whenever..." are not. Indeed, we can see this with sentences like
(16) It is rarely the case that, wherever Bianca goes, it's raining.
The (possible) moral is that we *can* sometimes posit (type-unselective?) variables--variables for *cases*, perhaps--when a quantifier demands it, despite there being very little to be said for positing it in the unembedded case.
Anyway, the biggest objection to the binding argument is OVERGENERATION. This comes in two flavors: syntactic and semantic. For a purely syntactic one, consider the Cappelen and Lepore examples with `2+2=4':
(17) Wherever Bianca goes, 2+2=4.
(18) Whenever I step outside, 2+2=4.
etc...
(17) and (18) are not semantically dependent, in the sense that their truth-conditions presumably do not differ from the unembedded `2+2=4': no one is forced to hold that the truth-conditions of mathematical statements varies NON-VACUOUSLY with times and places. But perhaps to stuff the unembedded sentence with these hidden variables is unpalatable, even if they are truth-conditionally inert.
Sennet writes that the semantic version of the complaint of overgeneration is one about predicted, but unattested, context-sensitivity. We consider:
(19) John is anorexic, but whenever his father cooks mushrooms, he eats.
The idea is that (19) doesn't mean `...he eats THEM.'
I'm pretty bewildered by this. Why would it? That would have to be a hidden variable for a direct object--not a time, but a thing--which couldn't be quantified over by `whenever', anyway. The appropriate version of the sentence would be:
(20) John is anorexic, but *whatever* his father cooks [t], he eats [t].
...now that IS a genuinely bound reading! But...it has nothing to do with (19). This is absolutely puzzling. Perhaps the only point is that we should beware of what Sennet has loosely termed ``semantic dependence" or ``dependent readings." An intuition of dependence may be merely pragmatic, related to salience: the *suggestion*, but not the content, of (19) includes the proposition that John eats his father's mushrooms whenever his father cooks mushrooms.
We have reached the end of the article. I have to say I'm still not clear on the connection between two things: (i) context-dependence, and (ii) hidden variables. If some words, like `tall', are context-sensitive, perhaps there is a hidden variable in them saturated by context. Perhaps these variables can be bound. Perhaps, then, we can test for bound readings. But we don't have quantifiers that bind contrast classes, so...uh...maybe not. Worse, presumably people are claiming that `tall' works relatively like an INDEXICAL---MacFarlane's nonindexical contextualism being a rather exotic view (and going unmentioned by Sennet.) But if that's true, the context-sensitive items SHOULDN'T be bindable--any more than indexicals are! It's a dogma of Kaplanian semantics that there are no natural language binders or shifters of indexicals: these would be `monsters.'
To conclude: what is free enrichment? Well, minimally, it's the positing of a hidden variable at LF. Boring view: so there's really an unarticulated constituent at LF. Weird crazy view: there isn't one there...AT FIRST...but pragmatic processes `insert' it!! Uh...that's pretty weird, since presumably facts in the meat of the language-module of your brain don't depend on how I interpret your sentence by applying Gricean maxims. I take it that the real puzzle of (1)---though maybe I've just got the debate all wrong---is whether we want to take `metaphysical' considerations to put stuff in LF. I've suggested elsewhere that the way to consider that question is to consider a language where there are no temporal operators like `always:'. More broadly: whether we can freely insert things in LF so that sentences come out to have the truth-conditions we think they should, in some sense, `really' have...when are intuitions about what truth-conditions they REALLY have are obviously contaminated by the binders, etc. we have in our *own* language!
Monday, November 1, 2010
Meeting Notes 11/3/10
1Q) Where did we leave of on the question of whether perceptual experiences have propositional contents?
1A) It seems uncontroversial to say that experiences have contents, in the sense that they tell us things. (And in the sense that verbs like "see" take direct objects.) But this is only neutral if we don't take "content" to simply be synonymous with "propositional content"; for example, Ming vases can tell us things about their owners, but Ming vases don't have propositional content. For sentences with perceptual verbs, we often have bare infinite complements, as in
John saw Mary cry. ["bare infinitive complement" for the verb "see"]
semanticists have proposed that the semantic value [[Mary cry]] could be: an event (Davidson, Higginbotham '93) or a situation (Moltmann.) Analyzing such locutions was a project of situation semantics. Ordinary English usage for the variety of verbs of experience is very wide here; the landscape of ordinary language is not nearly as uniform here as it is in e.g. the case of "believes" and the related family of doxastic verbs. Also, it is worth keeping in mind that our project is not first and foremost to give a correct semantics for e.g. "see"; it is to get at what "sees" and "looks"-statements are getting at.
2Q) LOT. When I tried to articulate a ''contextualist" response to Hellie's claim that exact-ers (ppl who think we perceive colors exactly but "shiftily"--e.g. Jackson and Pinkerton) are saddled with "slight nonveridicality" in experiences, MM asked me what in the story was supposed to be the analog of e.g. "red_29", the predicate that applies to patch b in context 1 but not in context 2. He suggested that the answer might be the syntactic token "red_29" in a LOT.
Why would one endorse a LOT? (Other than wanting to be a contextualist on the pattern of contextualists about natural language predicates?) I asked:
2.5Q) Could perceptual constancy be marshalled as data supporting such a view? ...Siegel so suggests in the SEP. A view would go something like this: the experience of a sunlight-dappled gray cabinet presents us with the same nominatum (the grayness of the cabinet) under different modes of presentation (the lighter or darker 'color' patches in our visual field, which help communicate to us that there is a uniformly colored gray cabinet before us.)
2A) Yes, that is how LOT could function here.
2.5A) Nonono! This is gravely confused. First of all, a LOT would most naturally be used to get *rid* of the need to make a Fregean sense-reference distinction amongst the contents of perception. The purpose of a Fregean sense-reference distinction is to explain how `a=a' is different from `a=b' *not in virtue of the sentences' syntactic features*:
"But this relation would hold between the names or signs only in so far as they named or designated something. It would be mediated by the connexion of each of the two signs with the same designated thing. But this is arbitrary. Nobody can be forbidden to use any arbitrarily producible event or object as a sign for something. In that case the sentence a = b would no longer refer to the subject matter, but only to its mode of designation; we would express no proper knowledge by its means. But in many cases this is just what we want to do." (Frege, Sinn Bedeutung Paragraph I)
But if we avail ourselves of a LOT, the syntactic feature explanation becomes viable again, in which case the postulation of senses is threatened with redundancy.
Moreover: perceptual constancy is not the right kind of phenomenon to be doing the work of motivating a sense-reference distinction for perceptual content. What we need is: (i) an informative identity and an uninformative identity; (ii) a reason to think the informativeness of the informative identity cannot be explained in terms of sameness of denotation [for then there would be no difference between `a=a' and `a=b']; (iii) a reason to think the informativeness of the identity cannot be explained in terms of sameness of sign [Frege's gloss: signs may be used however we like; however, in the sense in which this is true, knowledge is not, in general, expressed by such usages...it is not as if we may create whatever knowledge we like by using signs however we like.] [my gloss: in addition, such an account could not explain why some nonequivalent strings--e.g. 'my cat', 'the cat that belongs to me'--*don't* express something cognitively significant when conjoined by '='. We need something that cuts finer than denotation but not so fine as signs or symbols.]
Perceptual constancy is a phenomenon whereby the color of the cabinet is perceived as unchanging. So it isn't clear that we do have an informative identity here. To wit: it's not clear we have an analog of the cognitively significant "a=b" (would it be "region 1 is the same color as region 2"?) as well as the cognitively insignificant "a=a" (would it be "region 1 is the same color as region 1"?)
1A) It seems uncontroversial to say that experiences have contents, in the sense that they tell us things. (And in the sense that verbs like "see" take direct objects.) But this is only neutral if we don't take "content" to simply be synonymous with "propositional content"; for example, Ming vases can tell us things about their owners, but Ming vases don't have propositional content. For sentences with perceptual verbs, we often have bare infinite complements, as in
John saw Mary cry. ["bare infinitive complement" for the verb "see"]
semanticists have proposed that the semantic value [[Mary cry]] could be: an event (Davidson, Higginbotham '93) or a situation (Moltmann.) Analyzing such locutions was a project of situation semantics. Ordinary English usage for the variety of verbs of experience is very wide here; the landscape of ordinary language is not nearly as uniform here as it is in e.g. the case of "believes" and the related family of doxastic verbs. Also, it is worth keeping in mind that our project is not first and foremost to give a correct semantics for e.g. "see"; it is to get at what "sees" and "looks"-statements are getting at.
2Q) LOT. When I tried to articulate a ''contextualist" response to Hellie's claim that exact-ers (ppl who think we perceive colors exactly but "shiftily"--e.g. Jackson and Pinkerton) are saddled with "slight nonveridicality" in experiences, MM asked me what in the story was supposed to be the analog of e.g. "red_29", the predicate that applies to patch b in context 1 but not in context 2. He suggested that the answer might be the syntactic token "red_29" in a LOT.
Why would one endorse a LOT? (Other than wanting to be a contextualist on the pattern of contextualists about natural language predicates?) I asked:
2.5Q) Could perceptual constancy be marshalled as data supporting such a view? ...Siegel so suggests in the SEP. A view would go something like this: the experience of a sunlight-dappled gray cabinet presents us with the same nominatum (the grayness of the cabinet) under different modes of presentation (the lighter or darker 'color' patches in our visual field, which help communicate to us that there is a uniformly colored gray cabinet before us.)
2A) Yes, that is how LOT could function here.
2.5A) Nonono! This is gravely confused. First of all, a LOT would most naturally be used to get *rid* of the need to make a Fregean sense-reference distinction amongst the contents of perception. The purpose of a Fregean sense-reference distinction is to explain how `a=a' is different from `a=b' *not in virtue of the sentences' syntactic features*:
"But this relation would hold between the names or signs only in so far as they named or designated something. It would be mediated by the connexion of each of the two signs with the same designated thing. But this is arbitrary. Nobody can be forbidden to use any arbitrarily producible event or object as a sign for something. In that case the sentence a = b would no longer refer to the subject matter, but only to its mode of designation; we would express no proper knowledge by its means. But in many cases this is just what we want to do." (Frege, Sinn Bedeutung Paragraph I)
But if we avail ourselves of a LOT, the syntactic feature explanation becomes viable again, in which case the postulation of senses is threatened with redundancy.
Moreover: perceptual constancy is not the right kind of phenomenon to be doing the work of motivating a sense-reference distinction for perceptual content. What we need is: (i) an informative identity and an uninformative identity; (ii) a reason to think the informativeness of the informative identity cannot be explained in terms of sameness of denotation [for then there would be no difference between `a=a' and `a=b']; (iii) a reason to think the informativeness of the identity cannot be explained in terms of sameness of sign [Frege's gloss: signs may be used however we like; however, in the sense in which this is true, knowledge is not, in general, expressed by such usages...it is not as if we may create whatever knowledge we like by using signs however we like.] [my gloss: in addition, such an account could not explain why some nonequivalent strings--e.g. 'my cat', 'the cat that belongs to me'--*don't* express something cognitively significant when conjoined by '='. We need something that cuts finer than denotation but not so fine as signs or symbols.]
Perceptual constancy is a phenomenon whereby the color of the cabinet is perceived as unchanging. So it isn't clear that we do have an informative identity here. To wit: it's not clear we have an analog of the cognitively significant "a=b" (would it be "region 1 is the same color as region 2"?) as well as the cognitively insignificant "a=a" (would it be "region 1 is the same color as region 1"?)
Friday, October 29, 2010
Notes on Chierchia's Dynamic Binding
What keeps tripping me up about Chierchia's system is all the going back and forth between w's and p's. w's are assignment functions (to dynamic variables...the kind that can be co-bound across clause boundaries.) p's are sets of assignment functions. At any point in a discourse, there is a current w--a current assignment function. But also at any point in the discourse, there is a current p: this is a set of admissible continuations of the discourse. A sentence affects both: it can e.g. open up new 'card's in w, and it can also effect which ways the discourse can continue. A sentence may do each without the other. A plausible example of the first kind of sentence is "a thing_xi is self-identical". A plausible example of the second kind is "Bill smokes", or "I don't have any children."
We should ask ourselves, though, just how w is an assignment function. Typically a file (i) only records partial information about discourse referents (certainly, for example, not information that is uniquely identifying) and (ii) its domain is partial.
In order to get from our ordinary notion of an assignment to the more intuitive notion of a file (as described above), we could employ functions. A file like
1 = cat, black
2 = woman, tall, owner of 1
...could be associated with a *set* of assignment functions which satisfy it. If we called this a proposition p, then, for example, and would both be in p. But I'm not sure whether this is done! Investigation into this preliminary point is required!!
We should ask ourselves, though, just how w is an assignment function. Typically a file (i) only records partial information about discourse referents (certainly, for example, not information that is uniquely identifying) and (ii) its domain is partial.
In order to get from our ordinary notion of an assignment to the more intuitive notion of a file (as described above), we could employ functions. A file like
1 = cat, black
2 = woman, tall, owner of 1
...could be associated with a *set* of assignment functions which satisfy it. If we called this a proposition p, then, for example,
Wednesday, October 27, 2010
Byrne and Hilbert on color (in BBS)
...wherein we get a taste of what it is like to philosophize about color. In particular, we consider physicalism about color, as opposed to Eliminativism or Conventionalism. Our guiding background theory is representationalism:
What must colors be for them to be represented in our colored experiences? We assume that propositions--bearers of truth/falsity--are extractable from perceptual experiences in general: that "the proposition that *there is a red bulgy object on the table* is part of a subject's experience" when he looks at a red tomato (5). We assume that colors are represented in experience so conceived, and ask what colors must be for this to be possible.
What are the alternatives to Physicalism about color? Eliminativism: there ain't no colors. Dispositionalism: colors are psychological dispositions. To dispositionalism we pose "Berkeley's Challenge": why be dispositionalist about color and not dispositionalist about every other property (shape, size, etc.) that we can detect through the senses? (or more generally, that we can detect at all?) There are, of course, some things to say here---colors are only detectable via one sense-modality, physicalist explanations of phenomena that don't involve humans/animals rarely mention color, etc., but we set those aside for now. Primitivism: colors are not physicalist, not dispositionalist, and not nothing. Finally, Physicalism, which B&H endorse, identifies color with some physical property of (colored) objects. As they see it there are two main (related) objections to physicalism: physicalism cannot account for "the structure of phenomenal space" (they cite Boghossian and Velleman for this point), and, more particularly, that physicalism cannot account for the "opponent-process theory of vision", which presents several generalizations of which colors humans perceive in terms of the relative degrees of stimulation of their short-, medium-, and long-wavelength photoreceptors.
The first incarnation of physicalism is that colors are reflectance properties. A reflectance property for a given (uniformly colored) object is given as a graph with percentages from 0-100 on the y-axis and wavelengths on the x-axis. The height of the graph at a particular value of x indicates what proportion of incident light of wavelength x is reflected by the object. It appears that this is the best candidate for something which is both a physical property and a property to which we are sensitive in our color vision.
Three objections are raised: the first has to do with "metamers." These are pairs of objects whose reflectance graphs look very different but whose perceived colors are the same (the objects are indistinguishable under normal light.) B&H note that they will have to bundle different reflectance properties together to define *determinable* (as opposed to determinate) colors together anyway, so there is no objection in principle to identifying colors with sets of reflectance properties. These sets might not be, in any sense, "natural":
"Surfaces with grossly different reflectances can perceptually match even under fairly normal illuminants....so the reflectance-types that we identify with the colors will be quite uninteresting from the point of view of physics or any other branch of science unconcerned with the reactions of human perceivers. This fact does not, however, imply that these categories are unreal or somehow subjective. (11)"
...I take it this is a somewhat significant cost, since it seems that an account of colors in these terms would suggest that our color-concepts are highly gerrymandered. But perhaps this is the best we can do.
We then have a brief (quarantined) digression on transparent objects and colored lights. The authors suggest we shift to what they call "productance" (a sum of light reflected and light emitted) to account for these. They stress that although productance is relative to illumnants, the property productance enters into (the candidate property to be identified with color) is independent of any particular illuminant. There is also a somewhat shocking aside about so-called "related" and "unrelated" colors: related colors are only perceived when there are certain other colors in the scene. Apparently brown is such a color. I don't really understand B&H's reply, but it's got something to do with the fact that the perception of color constancy apparently relies a lot on the colors of other perceived objects in the environment.
On to the objection from phenomenal structure. Among the things to be explained are the distinction between binary hues (hues experienced as proportions of different colors--e.g. orange) and unique hues (e.g. red), as well as the opponent structure of the colors (green-red, yellow-blue, etc.) To respond to this challenge, B&H invoke the representational content of color-experiences:
"such heroism [the attempt to reject the explanatory demand from phenomenal structure] is not required. In our view, the phenomena of color similarity and opponency show us something important about the *representational content* of color experience--about the way the color properties are encoded by our visual systems And once we have a basic account of the content of color experience on the table, it will be apparent that there is no problem here for physicalism. (13)"
We complicate the picture--not the picture of color, as far as I can tell, but the picture of the content of color experiences. Before, experiences with "color content", given that color x is the physical property F, were simply of the form "a is F." Revised thesis: experience represent "objects as having proportions of hue-magnitudes." [NB here hue = color, in the physicalist sense defined and defended above.] So, for example, where F and G are primary hues, our experience tells us something like "a is both F and G, and it is twice as F as it is G."
Is there a cheat here? We started out wanting to account for e.g. the opponency of colors in terms of features of the colors themselves; instead, we wound up giving an account of the opponency of colors in terms of the content of a color-experience. Comparison: we could account for the "additive opponency" of certain pairs of integers (like 2 and -2) in terms of features of the numbers themselves---presumably this is what we do. Or we could give an account of the additive opponency of the pairs in terms of our experience. (I'm not sure what this would come to in the case of numbers.) Nothing can appear both squat and thin, since squatness consists in being wider than one is tall and thinness consists in being taller than one is wide; given this, we can account for the "opponency" of experiences of squat objects and experiences of thin objects by saying that squatness is the property of being wider than one is tall, and thinness is the property of being taller than one is wide. Moreover, we seem to have backed away from suggesting that we can actually detect reflectance properties---rather, we can merely detect relative ratios of reflectance properties. (Compare: we can actually perceive width and height and calculate squatness from these two things, or: we can only perceive the presence or absence of squatness.) This thought seems to be behind H&B's discussion of the lengths of sticks (14).
We now revisit several other objections to physicalism. The first comes from variation amongst color-perceiving subjects: which objects are perceived as "unique green" or balanced orange (a hue exactly as red as it is yellow) vary from subject to subject, often by a margin which is quite large relative to any individual subject. This fact leads some philosophers (or psychologists?--someone named Hardin) to espouse a kind of "conventionalism" about green: in the absence of consensus about which hue chip is unique green, "the question..can be answered only by convention (17)." Hardin is also an eliminativist, and his two thoughts seem connected here (although at first blush they are inconsistent--how can we just pick one when the real answer is "none"?) If the suggestion is that we must espouse an error theory about unique green (given the variation amongst color-perceivers, any choice of a hue chip as the real unique green will make a majority of perceivers wrong), and this error theory is unacceptable (it would be better to espouse eliminativism about colors), then the authors' response is simply that an error theory is not really so disastrous. They remind us that we are speaking of determinate rather than determinable properties. (We are not espousing an error theory for green---only for unique green.) They also remind us that we are not ready to espouse eliminativism about a host of other properties which are often perceived inaccurately (they use the example of spatial properties which are commonly misperceived by people with slightly mismatched retinal images across their two eyes.)
A host of responses that make reference to the peculiarity of the case of color: color is not detectable via other sense-modalities (if we are in error visually we cannot use other senses as independent checks--this distinguishes color from spatial properties). Secondly, color properties, if they exist, do not enter into any "data or theories of any sciences other than those concerned with animal behavior" (e.g., they only enter into intentional explanations--again, unlike spatial properties). So there seems to be a *more* significant cost to espousing an error theory for a color-property (and if physicalists are right, unique green *is* a color-property) than one of these other properties. Unique green will *not* enter in to very many intentional explanations--in the usual way, at least--if most perceivers are in error about which objects are unique green. (We could substitute *a belief that something is unique green* in our explanations of their behavior, but then, since the belief that A is F does not in general entail the existence of a real property F, we could do just as well without it.) (17). B&H's response seems to be this: in order to save the phenomena of ordinary perceivers, we need green to be a really existing property. But if green is a really existing property, then unique green exists.
(The response is a sort of "supertruth" response: on each acceptable adjudication of the boundaries of green [corresponding to each slightly different perceiver], some hue chip is unique green. So it is supertrue that some hue chip is green even if it isn't supertrue *of* any particular hue-chip that *it* is unique green. The weaker thing is all we need to be realists about green and unique green.)
Finally, we revisit the inverted spectrum. H&B suggest that the inverted spectrum thought-experiment is basically irrelevant to the thesis of physicalism about color as they have presented it. Their presentation relied on representationalism about color-experience. This can be true even if (as proponents of inverted spectrum scenarios often think) "what it's like" to have an experience is not exhausted by the representational content of that experience. H&B do point out, though, that to the extent that a "phenomenist" (an opponent of representationalism/intentionalism qua thesis about how representational content *exhausts* phenomenal content) believes that features of color like opponency and the binary/unique distinctions are features of "what it's like", and that's not representational, he will give a different account of these features than the representationalist does.
What must colors be for them to be represented in our colored experiences? We assume that propositions--bearers of truth/falsity--are extractable from perceptual experiences in general: that "the proposition that *there is a red bulgy object on the table* is part of a subject's experience" when he looks at a red tomato (5). We assume that colors are represented in experience so conceived, and ask what colors must be for this to be possible.
What are the alternatives to Physicalism about color? Eliminativism: there ain't no colors. Dispositionalism: colors are psychological dispositions. To dispositionalism we pose "Berkeley's Challenge": why be dispositionalist about color and not dispositionalist about every other property (shape, size, etc.) that we can detect through the senses? (or more generally, that we can detect at all?) There are, of course, some things to say here---colors are only detectable via one sense-modality, physicalist explanations of phenomena that don't involve humans/animals rarely mention color, etc., but we set those aside for now. Primitivism: colors are not physicalist, not dispositionalist, and not nothing. Finally, Physicalism, which B&H endorse, identifies color with some physical property of (colored) objects. As they see it there are two main (related) objections to physicalism: physicalism cannot account for "the structure of phenomenal space" (they cite Boghossian and Velleman for this point), and, more particularly, that physicalism cannot account for the "opponent-process theory of vision", which presents several generalizations of which colors humans perceive in terms of the relative degrees of stimulation of their short-, medium-, and long-wavelength photoreceptors.
The first incarnation of physicalism is that colors are reflectance properties. A reflectance property for a given (uniformly colored) object is given as a graph with percentages from 0-100 on the y-axis and wavelengths on the x-axis. The height of the graph at a particular value of x indicates what proportion of incident light of wavelength x is reflected by the object. It appears that this is the best candidate for something which is both a physical property and a property to which we are sensitive in our color vision.
Three objections are raised: the first has to do with "metamers." These are pairs of objects whose reflectance graphs look very different but whose perceived colors are the same (the objects are indistinguishable under normal light.) B&H note that they will have to bundle different reflectance properties together to define *determinable* (as opposed to determinate) colors together anyway, so there is no objection in principle to identifying colors with sets of reflectance properties. These sets might not be, in any sense, "natural":
"Surfaces with grossly different reflectances can perceptually match even under fairly normal illuminants....so the reflectance-types that we identify with the colors will be quite uninteresting from the point of view of physics or any other branch of science unconcerned with the reactions of human perceivers. This fact does not, however, imply that these categories are unreal or somehow subjective. (11)"
...I take it this is a somewhat significant cost, since it seems that an account of colors in these terms would suggest that our color-concepts are highly gerrymandered. But perhaps this is the best we can do.
We then have a brief (quarantined) digression on transparent objects and colored lights. The authors suggest we shift to what they call "productance" (a sum of light reflected and light emitted) to account for these. They stress that although productance is relative to illumnants, the property productance enters into (the candidate property to be identified with color) is independent of any particular illuminant. There is also a somewhat shocking aside about so-called "related" and "unrelated" colors: related colors are only perceived when there are certain other colors in the scene. Apparently brown is such a color. I don't really understand B&H's reply, but it's got something to do with the fact that the perception of color constancy apparently relies a lot on the colors of other perceived objects in the environment.
On to the objection from phenomenal structure. Among the things to be explained are the distinction between binary hues (hues experienced as proportions of different colors--e.g. orange) and unique hues (e.g. red), as well as the opponent structure of the colors (green-red, yellow-blue, etc.) To respond to this challenge, B&H invoke the representational content of color-experiences:
"such heroism [the attempt to reject the explanatory demand from phenomenal structure] is not required. In our view, the phenomena of color similarity and opponency show us something important about the *representational content* of color experience--about the way the color properties are encoded by our visual systems And once we have a basic account of the content of color experience on the table, it will be apparent that there is no problem here for physicalism. (13)"
We complicate the picture--not the picture of color, as far as I can tell, but the picture of the content of color experiences. Before, experiences with "color content", given that color x is the physical property F, were simply of the form "a is F." Revised thesis: experience represent "objects as having proportions of hue-magnitudes." [NB here hue = color, in the physicalist sense defined and defended above.] So, for example, where F and G are primary hues, our experience tells us something like "a is both F and G, and it is twice as F as it is G."
Is there a cheat here? We started out wanting to account for e.g. the opponency of colors in terms of features of the colors themselves; instead, we wound up giving an account of the opponency of colors in terms of the content of a color-experience. Comparison: we could account for the "additive opponency" of certain pairs of integers (like 2 and -2) in terms of features of the numbers themselves---presumably this is what we do. Or we could give an account of the additive opponency of the pairs in terms of our experience. (I'm not sure what this would come to in the case of numbers.) Nothing can appear both squat and thin, since squatness consists in being wider than one is tall and thinness consists in being taller than one is wide; given this, we can account for the "opponency" of experiences of squat objects and experiences of thin objects by saying that squatness is the property of being wider than one is tall, and thinness is the property of being taller than one is wide. Moreover, we seem to have backed away from suggesting that we can actually detect reflectance properties---rather, we can merely detect relative ratios of reflectance properties. (Compare: we can actually perceive width and height and calculate squatness from these two things, or: we can only perceive the presence or absence of squatness.) This thought seems to be behind H&B's discussion of the lengths of sticks (14).
We now revisit several other objections to physicalism. The first comes from variation amongst color-perceiving subjects: which objects are perceived as "unique green" or balanced orange (a hue exactly as red as it is yellow) vary from subject to subject, often by a margin which is quite large relative to any individual subject. This fact leads some philosophers (or psychologists?--someone named Hardin) to espouse a kind of "conventionalism" about green: in the absence of consensus about which hue chip is unique green, "the question..can be answered only by convention (17)." Hardin is also an eliminativist, and his two thoughts seem connected here (although at first blush they are inconsistent--how can we just pick one when the real answer is "none"?) If the suggestion is that we must espouse an error theory about unique green (given the variation amongst color-perceivers, any choice of a hue chip as the real unique green will make a majority of perceivers wrong), and this error theory is unacceptable (it would be better to espouse eliminativism about colors), then the authors' response is simply that an error theory is not really so disastrous. They remind us that we are speaking of determinate rather than determinable properties. (We are not espousing an error theory for green---only for unique green.) They also remind us that we are not ready to espouse eliminativism about a host of other properties which are often perceived inaccurately (they use the example of spatial properties which are commonly misperceived by people with slightly mismatched retinal images across their two eyes.)
A host of responses that make reference to the peculiarity of the case of color: color is not detectable via other sense-modalities (if we are in error visually we cannot use other senses as independent checks--this distinguishes color from spatial properties). Secondly, color properties, if they exist, do not enter into any "data or theories of any sciences other than those concerned with animal behavior" (e.g., they only enter into intentional explanations--again, unlike spatial properties). So there seems to be a *more* significant cost to espousing an error theory for a color-property (and if physicalists are right, unique green *is* a color-property) than one of these other properties. Unique green will *not* enter in to very many intentional explanations--in the usual way, at least--if most perceivers are in error about which objects are unique green. (We could substitute *a belief that something is unique green* in our explanations of their behavior, but then, since the belief that A is F does not in general entail the existence of a real property F, we could do just as well without it.) (17). B&H's response seems to be this: in order to save the phenomena of ordinary perceivers, we need green to be a really existing property. But if green is a really existing property, then unique green exists.
(The response is a sort of "supertruth" response: on each acceptable adjudication of the boundaries of green [corresponding to each slightly different perceiver], some hue chip is unique green. So it is supertrue that some hue chip is green even if it isn't supertrue *of* any particular hue-chip that *it* is unique green. The weaker thing is all we need to be realists about green and unique green.)
Finally, we revisit the inverted spectrum. H&B suggest that the inverted spectrum thought-experiment is basically irrelevant to the thesis of physicalism about color as they have presented it. Their presentation relied on representationalism about color-experience. This can be true even if (as proponents of inverted spectrum scenarios often think) "what it's like" to have an experience is not exhausted by the representational content of that experience. H&B do point out, though, that to the extent that a "phenomenist" (an opponent of representationalism/intentionalism qua thesis about how representational content *exhausts* phenomenal content) believes that features of color like opponency and the binary/unique distinctions are features of "what it's like", and that's not representational, he will give a different account of these features than the representationalist does.
Tuesday, September 21, 2010
Nonindexical Contextualism and content
Today, we look askance at the word "content". What is this term, from philosophy of mind, doing in our semantic theorizing? We are not sure; our suspicions are roused.
Yet Prof. MacFarlane talks at length about content in "Nonindexical contextualism," where he argues for the existence and viability of a view on which epistemic operators are context-sensitive without being indexical. Translation into our suspect terminology: an epistemic standard parameter may play a circumstance-determinative role without playing a content-determinative role in our semantics.
From his discussion, the following, at least, are clear about content:
*the content of a sentence-at-a-context is intuitively identified with a proposition
*sentences with indexicals express different propositions (hence, have different contents) at different contexts.
*the content of a sentence determines its truth-value at a context of use.
...From this, it seems that the right thing to conclude is that content of a sentence-at-a-context is just its semantic intension. All the indexicals are, so to speak, "filled in", but the the resulting intension has not yet been evaluated at the circumstance of the context, so the intension has not yet been reduced to an extension (either T or F.)
Another way to get a bead on content, suggested by MacFarlane's discussion, is to look at the dispute between Temporalism and Eternalism. For Eternalists, the time of the context gets into the content of tensed sentences like "Socrates is sitting":
"On the Eternalist's view, the sentence ["Socrates is sitting"] varies in truth-value across times because it expresses different propositions at different times." (4)
This suggests the following gloss on the difference between Eternalism and Temporalism in terms of semantic values:
(Temp) [[Socrates is sitting]]^c_{\varnothing}* = \lambda w. \lambda t. Socrates is sitting in w at t
(Eter) [[Socrates is sitting]]^c_{\varnothing} = \lambda w . \lambda t . Socrates is sitting in w at t_c.
...hence on this view what it means for the Eternalists and Temporalists to disagree about what proposition "Socrates is sitting" expresses is for them to disagree on the intension of the sentence. Behold the "t_c" in the Eternalist's semantic entry; this is an indexical, just as "speaker_c" would be the meaning of "I" or "loc_c" would be the meaning of "here." So, on this entry, the Eternalist just thinks that "Socrates is sitting" is synonymous with "Socrates is sitting now."
What I find confusing about this is that I am unable to give a proper semantic entry for temporal operators on the eternalist's view. "Socrates is sitting" does NOT behave like "Socrates is sitting now" in that, of course, [[It will always be the case that Socrates is sitting]] is not the same as [[It will always be the case that Socrates is sitting now.]] Any eternalist view must account for this difference; the Eternalist cannot be so easily refuted as that!
...He must account for it in the same way that a possible worlds theorist accounts for the intuitive truth conditions of "Snow is white" as opposed to "Snow is actually white." He must hold that unembedded assertions like "Snow is white" are as a default evaluated at the world of the context, but that they are still shift-able in the scope of modal operators. I can see two ways to do this. One is to mimic, for our intuitive notion of content, the semanticists intensional type-lift: hold that content is usually extension, unless it is *forced* to be intension by the presence of a model operator. Hence: an unembedded "snow is white" utterance is true if snow is white in w_c, yet the contribution "snow is white" makes in the scope of modal operators does not refer us back to w_c.
The problem with this is that it makes nonsense of the other things MacFarlane says about content. For example, he says of the sentence "tomorrow comes after today" that it expresses different contents at different contexts, while having the same truth-value at every context. However, if the content of an unembedded expression is its EX-tension, then it cannot vary in this way.
The only other way I can see is to hold that content is what Prof. Yalcin calls "centered diagonal content", where this is lambda-abstraction over the c parameter. Hence:
(Temp) [[Socrates is sitting]]^wt_{\varnothing}** = \lambda c. Socrates is sitting at w_c
(Eter) [[Socrates is sitting]]^wt_{\varnothing} = \lambda c . Socrates is sitting at w_c and t_c.
Note once again the absence of t_c from (Temp). What, now, would the difference between (Temp) and (Eter) come to? Almost nothing, which is, perhaps, the point...It seems only to support the following intuition:
"If I had said "Socrates is sitting" at another time, it would have expressed a different content."
...this is true for (Eter) and not for (Temp). These creatures, (Eter) and (Temp), are NOT the arguments of temporal operators. What *are* the intensions on this view? It must be...
(Temp) [[Socrates is sitting]]^c_{\varnothing} = \lambda w . Socrates is sitting in w
(Eter) [[Socrates is sitting]] ^c_{\varnothing} = \lambda w . \lambda t . Socrates is sitting in w at t
Now this is pretty odd. On this version of temporalism, sentence truth looks like this:
A sentence s is true at a context c iff [[S]] is true at w_c and t_c. [hence there need be no temporal content "in" S.]
(A sentence s is true at a context c iff the proposition expressed by S is true when evaluated at the circumstance of C. = (25), pg. 21.)
And temporal operators look...metalinguistic, I guess, like this:
[[ALWAYS \phi]]^cwt = \lambda w . \forall c' s.t. w_c' = w_c, [[\phi]] expresses a truth at the circumstance determined by c; [[\phi]]^w_c, t_c is true.
...this view looks very strange to me, though we should note of an analogous move for epistemic standard parameters it is widely conceded that there *are* no shifters. The arguments in favor of such a view must mostly be content-based ones in the phil-mind sense, because semantically speaking, it's ugly.*** (Perhaps the right thing to say about this ugliness is that we are simply no longer speaking about any kind of semantic value or anything straightforwardly derivable from a semantic value.)
Here is such a consideration: the propositions we believe (= the contents of sentence at a context) intuitively don't determine truth "all by themselves." Sam believes it is 0 degrees--is that belief true or false? Well, we don't know until we know the time and place his belief 'concerns'. We also need to know what world he's in, and intuitively his belief isn't about worlds:
"One might respond to these considerations by bringing the world of the context of use into the *content* of Sam's thought. But intuitively, Sam could have had a thought with the same content even if the world had been very different." (16)
According to Temporalism, both worlds and times play a circumstance- but not content-determining role. For Eternalism, times play a content-as-well-as-circumstance determining role. Yet I am puzzled about how to make this work in the formal semantics, because I am puzzled by how content is supposed to interact with intensions. We have a good argument that intensions must have an *open* (hence shiftable) time-parameter, but whether this legislates that time does not play a content-determining role depends on what the relationship between intensions and contents is. In the epistemic standards case, once it is conceded that there are no shifters, we don't need an open (hence shiftable) time-parameter in the intension. Perhaps we don't need one *at all*, and it is this that nonindexical contextualism amounts to. The difference then would not be between a *free* t-parameter and a [contextually] *bound* t-parameter, but rather a difference between a [contextually] *bound* e-parameter and...no e-parameter at all.
******
*e.g., the intension of the sentence, rather than the extension. (Following Heim and von Fintel.) Note the index here comprises world-time ordered pairs.
**Generalizing the pattern to mean abstraction over c but not w and t? Probably this is abuse of notation.
***Note that this won't work for the world parameter anyway, for familiar reasons: it is not sufficient for the truth of the sentence "necessarily p" that p express a truth at every context.
*******
MacFarlane, J. "Nonindexical Contextualism." Synthese 166, 2009.
Yalcin, S. "Notes on semantics, context, and content". Handout at UC Berkeley for Phil 290-5, 9/16/2010.
Yet Prof. MacFarlane talks at length about content in "Nonindexical contextualism," where he argues for the existence and viability of a view on which epistemic operators are context-sensitive without being indexical. Translation into our suspect terminology: an epistemic standard parameter may play a circumstance-determinative role without playing a content-determinative role in our semantics.
From his discussion, the following, at least, are clear about content:
*the content of a sentence-at-a-context is intuitively identified with a proposition
*sentences with indexicals express different propositions (hence, have different contents) at different contexts.
*the content of a sentence determines its truth-value at a context of use.
...From this, it seems that the right thing to conclude is that content of a sentence-at-a-context is just its semantic intension. All the indexicals are, so to speak, "filled in", but the the resulting intension has not yet been evaluated at the circumstance of the context, so the intension has not yet been reduced to an extension (either T or F.)
Another way to get a bead on content, suggested by MacFarlane's discussion, is to look at the dispute between Temporalism and Eternalism. For Eternalists, the time of the context gets into the content of tensed sentences like "Socrates is sitting":
"On the Eternalist's view, the sentence ["Socrates is sitting"] varies in truth-value across times because it expresses different propositions at different times." (4)
This suggests the following gloss on the difference between Eternalism and Temporalism in terms of semantic values:
(Temp) [[Socrates is sitting]]^c_{\varnothing}* = \lambda w. \lambda t. Socrates is sitting in w at t
(Eter) [[Socrates is sitting]]^c_{\varnothing} = \lambda w . \lambda t . Socrates is sitting in w at t_c.
...hence on this view what it means for the Eternalists and Temporalists to disagree about what proposition "Socrates is sitting" expresses is for them to disagree on the intension of the sentence. Behold the "t_c" in the Eternalist's semantic entry; this is an indexical, just as "speaker_c" would be the meaning of "I" or "loc_c" would be the meaning of "here." So, on this entry, the Eternalist just thinks that "Socrates is sitting" is synonymous with "Socrates is sitting now."
What I find confusing about this is that I am unable to give a proper semantic entry for temporal operators on the eternalist's view. "Socrates is sitting" does NOT behave like "Socrates is sitting now" in that, of course, [[It will always be the case that Socrates is sitting]] is not the same as [[It will always be the case that Socrates is sitting now.]] Any eternalist view must account for this difference; the Eternalist cannot be so easily refuted as that!
...He must account for it in the same way that a possible worlds theorist accounts for the intuitive truth conditions of "Snow is white" as opposed to "Snow is actually white." He must hold that unembedded assertions like "Snow is white" are as a default evaluated at the world of the context, but that they are still shift-able in the scope of modal operators. I can see two ways to do this. One is to mimic, for our intuitive notion of content, the semanticists intensional type-lift: hold that content is usually extension, unless it is *forced* to be intension by the presence of a model operator. Hence: an unembedded "snow is white" utterance is true if snow is white in w_c, yet the contribution "snow is white" makes in the scope of modal operators does not refer us back to w_c.
The problem with this is that it makes nonsense of the other things MacFarlane says about content. For example, he says of the sentence "tomorrow comes after today" that it expresses different contents at different contexts, while having the same truth-value at every context. However, if the content of an unembedded expression is its EX-tension, then it cannot vary in this way.
The only other way I can see is to hold that content is what Prof. Yalcin calls "centered diagonal content", where this is lambda-abstraction over the c parameter. Hence:
(Temp) [[Socrates is sitting]]^wt_{\varnothing}** = \lambda c. Socrates is sitting at w_c
(Eter) [[Socrates is sitting]]^wt_{\varnothing} = \lambda c . Socrates is sitting at w_c and t_c.
Note once again the absence of t_c from (Temp). What, now, would the difference between (Temp) and (Eter) come to? Almost nothing, which is, perhaps, the point...It seems only to support the following intuition:
"If I had said "Socrates is sitting" at another time, it would have expressed a different content."
...this is true for (Eter) and not for (Temp). These creatures, (Eter) and (Temp), are NOT the arguments of temporal operators. What *are* the intensions on this view? It must be...
(Temp) [[Socrates is sitting]]^c_{\varnothing} = \lambda w . Socrates is sitting in w
(Eter) [[Socrates is sitting]] ^c_{\varnothing} = \lambda w . \lambda t . Socrates is sitting in w at t
Now this is pretty odd. On this version of temporalism, sentence truth looks like this:
A sentence s is true at a context c iff [[S]] is true at w_c and t_c. [hence there need be no temporal content "in" S.]
(A sentence s is true at a context c iff the proposition expressed by S is true when evaluated at the circumstance of C. = (25), pg. 21.)
And temporal operators look...metalinguistic, I guess, like this:
[[ALWAYS \phi]]^cwt = \lambda w . \forall c' s.t. w_c' = w_c, [[\phi]] expresses a truth at the circumstance determined by c; [[\phi]]^w_c, t_c is true.
...this view looks very strange to me, though we should note of an analogous move for epistemic standard parameters it is widely conceded that there *are* no shifters. The arguments in favor of such a view must mostly be content-based ones in the phil-mind sense, because semantically speaking, it's ugly.*** (Perhaps the right thing to say about this ugliness is that we are simply no longer speaking about any kind of semantic value or anything straightforwardly derivable from a semantic value.)
Here is such a consideration: the propositions we believe (= the contents of sentence at a context) intuitively don't determine truth "all by themselves." Sam believes it is 0 degrees--is that belief true or false? Well, we don't know until we know the time and place his belief 'concerns'. We also need to know what world he's in, and intuitively his belief isn't about worlds:
"One might respond to these considerations by bringing the world of the context of use into the *content* of Sam's thought. But intuitively, Sam could have had a thought with the same content even if the world had been very different." (16)
According to Temporalism, both worlds and times play a circumstance- but not content-determining role. For Eternalism, times play a content-as-well-as-circumstance determining role. Yet I am puzzled about how to make this work in the formal semantics, because I am puzzled by how content is supposed to interact with intensions. We have a good argument that intensions must have an *open* (hence shiftable) time-parameter, but whether this legislates that time does not play a content-determining role depends on what the relationship between intensions and contents is. In the epistemic standards case, once it is conceded that there are no shifters, we don't need an open (hence shiftable) time-parameter in the intension. Perhaps we don't need one *at all*, and it is this that nonindexical contextualism amounts to. The difference then would not be between a *free* t-parameter and a [contextually] *bound* t-parameter, but rather a difference between a [contextually] *bound* e-parameter and...no e-parameter at all.
******
*e.g., the intension of the sentence, rather than the extension. (Following Heim and von Fintel.) Note the index here comprises world-time ordered pairs.
**Generalizing the pattern to mean abstraction over c but not w and t? Probably this is abuse of notation.
***Note that this won't work for the world parameter anyway, for familiar reasons: it is not sufficient for the truth of the sentence "necessarily p" that p express a truth at every context.
*******
MacFarlane, J. "Nonindexical Contextualism." Synthese 166, 2009.
Yalcin, S. "Notes on semantics, context, and content". Handout at UC Berkeley for Phil 290-5, 9/16/2010.
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