Friday 23 February 2007

What (Else) is Going On...

First, I should call everyone's attention to the most recent issue of the Philosopher's Carnival, here, which is being hosted by Trent Dougherty. I'm really liking the tone and quality of posts in the most recent Carnivals, especially the previous issue, here. Let's hope these high quality Carnivals continue.

Update: In the comments of the Carnival there is a short exchange between Trent and Clayton Littlejohn about my post, in which Clayton comes to my defence. Surprise, surprise...I happen to agree with Clayton on this one (even if I am somewhat of an 'innie').

Second, all you McDowell fans can find an interesting paper, here, by Adam who brings the theoretical apparatus of Virtue Epistemology to bear on McDowell's theory of knowledge.

Third, I owe a word of gratitude to Brian Leiter for mentioning my blog on his Leiter Reports. During the week my blog was featured I had over 900 new visitors! Hopefully this increase in blog traffic will eventually translate into more feedback. Please? Oh, and my humblest apologies to Jerry Fodor for whatever part I played in inspiring Brian's snide remark.

Tuesday 13 February 2007

The Wright Objection

Following J. M. Hinton [1973], Paul Snowdon [1990] has argued that indistinguishable veridical and hallucinatory perceptual experiences belong to fundamentally different genera. Thus, veridical perceptual experiences (henceforth e1) are of one sort while hallucinatory perceptual experiences (henceforth e2) are of another fundamentally different sort, the only thing common to both being that they are introspectively indistinguishable from each other. The difference between e1 and e2 is, for Snowdon, is rooted in the fact that perceptual experiences are essentially relational.

John McDowell takes up Snowdon’s disjunctive conception and applies its insights to epistemological questions relating to our perceptual beliefs.1 According to McDowell, the epistemological upshot of the disjunction between e1 and e2 is that e1 places us in a better epistemic position than e2 does. On its own, this claim hardly seems controversial. For example, a reliabilist would agree that e1 places us in a better epistemic position than e2 since veridical perceptual experiences are a reliable source of true beliefs while hallucinations are not. However, what is most striking about McDowell’s claim that e1 puts us in a better epistemic position to e2 is that he rejects (extreme) forms of epistemic externalism:
[O]ne’s epistemic standing on some question cannot intelligibly be constituted, even in part, by matters blankly external to how it is with one subjectively. For how could such matters be other than beyond one’s ken? And how could matters beyond one’s ken make any difference to one’s epistemic standing? [McDowell 1998, p. 390]
I interpret ‘how it is with one subjectively’ to mean from the subject’s point of view. However, many critics have insisted that if e1 and e2 are subjectively indistinguishable, then from the subject’s point of view e1 could not possibly put one in a better epistemic position than e2. In this post I will sketch the version of this criticism put forward by Crispin Wright [2002].

Wright presents the following challenge to McDowell’s disjunctive analysis. Suppose S came to hold the demonstrative belief that that is an F. Does S’s justification for believing that that is an F transmit to the claim that S is not merely having a hallucination of an F? According to Wright, there is a ‘strong intuition’ that it does not since we have done nothing to rule out the unpropitious possibility [2002, p. 342]. Moreover, since ex hypothesi the hallucination in question is subjectively indistinguishable from a veridical perceptual experience, there is no way for the subject, based on that experience, to know that she is not suffering from a hallucination rather than having a veridical perceptual experience.

Wright applies the above argument to disjunctivism by appealing to the following four presuppositions, which he describes as the disjunctive template [Ibid, p. 343]:
(i) that A entails B;

(ii) that my justification2 for A consists in my being in a state which is subjectively indistinguishable from a state in which the relevant C would be true;

(iii) that C depicts a situation of a general kind incompatible with the reliable operation of the cognitive capacities involved in generating the putative warrant for A; and

(iv) that C would be true if B were false.
We may fill in the details of the disjunctive template thus: Let A be the proposition that that is an F. Let B be the entailed proposition that that is not a hallucination of an F; and let C take the form of a generalisation of the negation of B: It is not the case that I am having a perfect hallucination of an F. Given the above disjunctive template the question, according to Wright, is
What…can justify me in taking it that I have a warrant for A? Why not just reserve judgement and stay with the more tentative disjunction, Either (I have a warrant for) A, or C? [Ibid].
Wright maintains that to get beyond the disjunction [A V C], we must somehow discount C. That is, we can only maintain that ‘that is an F’ if we can discount the possibility that ‘that is not an F but merely an indistinguishable hallucination of an F’. However, to be entitled to discount C I must also be entitled to discount ~B since, ex hypothesi, C is merely the generalisation of B’s negation. However, to discount ~B I must have some prior entitlement to B independent of its entailment by A. Consequently, on pain of circularity, my justification for A fails to transmit to B.

The upshot of the above analysis is that, given the possibility of there being hallucinations that are subjectively indistinguishable from veridical perceptual experiences, we cannot take ourselves to be justified (as far as our perceptual beliefs are concerned) in believing anything beyond the disjunction [A V C].

We may further unpack the Wright objection as follows: Let us presuppose an internalist conception of epistemic justification such that for S to be justified in believing that P means that S has subjective access to that which constitutes her justification for believing that P. Let [E1 … En] stand for the maximal set of subjective properties of some experience e1. If there is some experience, e2, which is subjectively indistinguishable from e1, then e2 must also possess [E1 … En], or at least so the thought goes. (I am here assuming that the circle encompassing what is introspectively accessible is coextensive with the maximal set of subjective properties of a given experience.) Given the internalist requirement that S’s justification for believing that P must be introspectively accessible, S’s justification for believing that P must be derived from [E1 … En] or some subset thereof. Since e1 and e2 share [E1 … En] in common, and given the internalist requirement that S’s justification for believing that P be derived from [E1 … En], any evidence derived from e1 in support of S’s believing that P can also be derived from e2 in support of S’s believing that P. Thus, insofar as e1 and e2 are subjectively indistinguishable, there can be no difference between what being in e1 makes S justified in believing and what being in e2 makes S justified in believing. Ergo, e1 does not put S in a better epistemic position, from an internalist perspective, than e2.


Endnotes:

1 It should be borne in mind that there are a number of significant differences between Snowdon’s and McDowell’s formulation of disjunctivism. For example, Snowdon focuses on locutions of object-perception, ‘S sees o’, while McDowell is interested in locutions of fact-perception, ‘S sees that p.’ Following McDowell, I will be using a version of fact-perception statements, ‘S sees that that is an F’.

2 Wright uses the word ‘warrant’.


References:
Hinton, J.M. [1973]. Experiences. Clarendon Press: Oxford.

McDowell, J. [1998], ‘Criteria, Defeasibility, and Knowledge’, Meaning, Knowledge, and Reality, 369-94, London: Harvard University Press.

Snowdon, P. F. [1990], “The Objects of Perceptual Experience” Proceedings of the Aristotelian Society Supplementary Volume 64: 121–150.

Wright, C. [2002].‘(Anti-)Sceptics Simple and Subtle: G.E. Moore and John McDowell’, Philosophy and Phenomenological Research 65: 330 – 48.

Sunday 4 February 2007

Moore On Sense Data

One of the central questions in the philosophy of perception is: what are the objects of perception? One way to interpret the locution ‘objects of perception’ is in terms of what it is that we are immediately aware of in the act of perceiving. In the early 20th century the traditional answer to this question was ‘sense data’ (henceforth SD). Thus, Moore defines SD as that which we ‘directly apprehend’ in perception [p. 46 ff*]. A striking feature of Moore’s account of SD is that he appears to remain open to the possibility that SD are mind-independent [p. 31, 43-5]. For example, Moore opines that SD may continue to exist even when we do not perceive them [p. 31], in which case their existence would not be dependent on the mind of the perceiver. In this regard, Moore’s conception of SD differs slightly from that of most contemporary philosophers who view mind-dependence as a fundamental feature of SD (a fact which Moore [p. 40-3] himself acknowledges).

Moore points out that when we combine (1) the assumption that in perceptual experience we only directly apprehend SD, with (2) the standard view of SD as mind-dependent, we appear to quickly run into epistemological difficulty [p. 48]. The former claim makes SD the basis for our perceptual beliefs while the latter allows for the possibility that SD only exist in the mind of the perceiver without any corresponding physical objects. Together, they appear to invite scepticism regarding our belief in the existence of physical objects since said belief is based on something that is compatible with there being no physical object. Significantly, the above line of reasoning rests on the equating of mind-dependence with object-independence (and by ‘object-independence’ I mean the thesis that SD (can) exists independently of any corresponding physical object). However, it is conceivable that SD could be simultaneously mind-dependent and object-dependent (for example, we may conceive of SD as arising out of some type of interaction between the mind and object). Moore seems to conflate mind-dependence and object-independence [p. 48], though he does avoid making the inverse mistake of assuming that mind-independence equals object-dependence (more on the latter claim below).

At times Moore seems to lean toward the view that SD may actually be identical to the physical surfaces of objects, but at no point does he ever endorse this view. Such reluctance on the part of Moore seems warranted since identifying SD with the surfaces of objects falls prey to one of the challenges that led philosophers to posit SD in the first place—namely, the problem of hallucinations. Since in the case of hallucinations, unlike illusions, there is no object present at all, there is nothing for SD to adhere to. Thus, even if he were to concede that SD are mind-independent, if he is to account for hallucinations, Moore must maintain that SD are object-independent (as he does in fact do). Another question that Moore appears to remain neutral on is whether SD are physical or non-physical entities. If the former, then Moore seems forced to identify them with the surfaces of objects (a prospect we have already deemed unattractive). However, if he regards them as non-physical then Moore seems faced with the difficulties of explaining what exactly they are and how could they interact causally (if at all) with our sensory faculties. In sum, it remains unclear whether Moore regarded SD as mind-dependent or mind-independent, or physical or non-physical. But this much seems clear: whatever they are, SD must (by Moore’s lights) be object-independent [p. 50].

Question: Does Moore ever come to a final position on whether (1) are SD mind-independent or mind-dependent or (2) are SD physical or non-physical?

*All citations refer to the first chapter of Moore’s Some Main Problems of Philosophy.

Friday 2 February 2007

"Internalising" McDowell

In my previous post, I addressed the main methodological objection to my claim that McDowell is a J-internalist. In this post, I will attempt to address what I take to be the primary theoretical objection to this proposal.

But first, what textual evidence do I have for holding that McDowell is a J-internalist? Two of the more suggestive passages are as follows:
I agree…that we lose the point of invoking the space of reasons if we allow someone to possess a justification even if it is outside his reflective reach. [McDowell 1998b, p. 418]
And:
[O]ne’s epistemic standing on some question cannot intelligibly be constituted, even in part, by matters blankly external to how it is with one subjectively. For how could such matters be other than beyond one’s ken? And how could matters beyond one’s ken make any difference to one’s epistemic standing? ([McDowell 1998a] p. 390)
I interpret the locution ‘how it is with one subjectively’, as an umbrella term for the sorts of things that are typically taken to be internally available to one, such as one’s thoughts, beliefs etc. By McDowell’s lights the circle delineating what is subjectively available to one exhausts that which may serve as a justifier for one’s beliefs. When this idea is restated in the argot of possible worlds, we arrive at McDowellian J-internalism, (M-Int):
(M-Int) For all agents S1 and S2 and worlds W1 and W2, if S1 in W1 and S2 in W2 are identical in terms of how things are with them subjectively, then S1 and S2 are identical in all respects relevant to the justification of their beliefs.
Now the main theoretical objection to my proposal can be put as follows: McDowell could not possibly be a J-internalist since he subscribes to a type of content externalism (henceforth, C-externalism) and C-externalism entails the falsehood of J-internalism. This objection hardly seems surprising when we juxtapose the popular construal of J-internalism and C-externalism:
(J-Int) For all subjects S1 and S2 and worlds W1 and W2, if S1 in W1 and S2 in W2 are identical in the intrinsic properties on which their thoughts supervene, then S1 and S2 are identical in all respects relevant to the justification of their beliefs.
(C-Ext) There are subjects S1 and S2 and worlds W1 and W2, such that S1 in W1 and S2 in W2 have the same intrinsic properties but differ in the content of their thoughts.
There is a conflict between (J-Int) and (C-Ext) since the former requires all subjects who are identical in terms of their intrinsic properties to have the same justificatory properties, while the latter allows subjects with identical intrinsic properties to differ with regards to the justificatory properties of their beliefs. For example, consider two subjects, S1 and S2, who are identical in terms of their intrinsic properties, but occupy different external environments, W1 and W2, respectively. Suppose S1 and S2 both performed the following valid deduction:
(A) Water is a liquid.
(B) Water is potable.
(C) Therefore, water is a potable liquid.
According to (C-Ext), the thoughts expressed by sentences (A)—(C) are different for S1 and S2. This is because S1’s thoughts are individuated in terms of water while S2’s thoughts are individuated in terms of twater. The distinct pairs of thought that S1 and S2 express by (A) and (B) are relevant to the justification of the pair of beliefs they respectively express by (C). Consequently, S1 and S2 satisfy the antecedent of (J-Int), since ex hypothesi they are identical in terms of their intrinsic properties, but fail to satisfy the consequent—to wit, they differ in some respects relevant to the justification of their beliefs. Thus, if (C-Ext) is true, then (J-Int) must be false.

There is a strong temptation to assume that this line of argument also impugns (M-Int). But if we take seriously McDowell’s notion of object-dependent thought there is no obvious inconsistency between (M-Int) and (C-Ext). According to McDowell, how it is with one subjectively is in part constituted by objects in one’s environment. For instance, in the Twin Earth examples generated by (C-Ext), the object-dependent thoughts expressed by (A) and (B) in the foregoing deductive inference are different for S1 and S2. Hence, by McDowell’s lights, S1 and S2 fail to satisfy the antecedent of (M-Int) since S1 and S2 are not identical with regards to how things are with them subjectively. Thus, McDowell can, without contradiction, continue to hold to (M-Int) while subscribing to (C-Ext).


References:

McDowell, J. (1998a), ‘Criteria, Defeasibility, and Knowledge’, Meaning, Knowledge, and Reality, 369-94, London: Harvard University Press.

McDowell, J. (1998), ‘Knowledge By Hearsay’, Meaning, Knowledge, and Reality, 414-43, London: Harvard University Press.