Daniel Kostić Daniel Kostić THE EXPLANATORY GAP ACCOUNT AND INTELLIGIBILITY OF EXPLANATION1 SUMMARY: This paper examines the explanatory gap account. The key notions for its proper understanding are analysed. In particular, the analysis is concerned with the role of "thick" and "thin" modes of presentation and "thick" and "thin" concepts which are relevant for the notions of "thick" and "thin" conceivability, and to that effect relevant for the gappy and non-gappy identities. The last section of the paper discusses the issue of the intelligibility of explanations. One of the conclusions is that the explanatory gap account only succeeds in establishing the epistemic gap. The claim that psychophysical identity is not intelligibly explicable, and thus opens the explanatory gap, would require an independent argument which would prove that intelligible explanations stem only from conceptual analysis. This, I argue, is not the case. KEY WORDS: The explanatory gap, the epistemic gap, modes of presentation, conceivability, possibility, intelligibility of explanation. "On the one hand, we have excellent reason for thinking that conscious experience must be reducible, in the requisite sense, to a physical phenomenon, and, on the other hand, we don't see how it could be." (Levine 2001, p. 175). This paper is concerned with the explanatory gap account (Levine 1983, 1993, 2001). At its core the problem we are about to tackle is that physicalism could be true and we still would not be able to know how that could be. As Joseph Levine puts it:"...we have excellent reasons for thinking that mental phenomena, including conscious experience, must be a species of physical/natural phenomena. On the other hand, we also have excellent reasons for thinking conscious experience cannot be captured in physical/natural terms" (Levine 2001, pp. 9–10). As we shall see, Levine powerfully argues that although the entailment from conceivability to metaphysical possibility of zombies in the conceivability arguments, cannot be THEORIA 3 UDK 165.3/.4 BIBLID 0351–2274 : (2011) : 54 : p. 27–42 Originalni naučni rad Original Scientific Paper 1 I would like to thank Stephen Tiley for proofreading this paper and for providing very useful comments on it. 28 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 29 established, materialism is still not off the hook because this claim needs a further argument that would explain how the same property can instantiate two semantically different concepts. I start off laying out the explanatory gap account by examining some technical terms Levine (2001) has introduced. The first on our agenda is the difference between "thick" and "thin" modes of presentation and "thick" and "thin" concepts. After that I will be examining notions of "thick" and "thin" conceivability, ascriptive and non-ascriptive modes of presentation, then gappy and non-gappy identities, and finally in the last section I will be concerned with the issue of the intelligibility of explanations. Let's begin with "thick" and "thin" concepts and modes of presentation. 1. Thick and thin concepts and modes of presentations To understand this idea one must realize that the ways in which we conceptually grasp properties determine the way in which the explanation of a given phenomenon works. One can think of the ways in which we think about content of our experience as modes of presentation (Levine 2001, p. 8). Levine claims that this point becomes really obvious when one considers the modes of presentation that are employed when we think about natural kinds and about qualities of our own experiences. In the case of natural kinds the mode of presentation is representationally "thin", i.e. our cognitive relation to the content of experience of a natural kind bears nothing substantial or determinate apart from the informational presentation and perhaps relation to other presentationally "thin" properties. Take for example a concept of a cat. There are two things that are relevant for the mode of presentation here. On the one hand, there is a mental symbol "cat" and on the other hand, there is some kind of a nomic relation between that symbol and a property of being a cat. Obviously, the symbol "cat" plays some cognitive role, but that is not determinate for the content of a concept of cat. What is more important for the content of a natural kind concept is its relation to "cathood". In this sense, there is nothing substantial or determinate about our cognitive relation with natural kinds concepts and that is why they are presentationally "thin". Contrary to this, our cognitive relation to the content of phenomenal experience is substantive and determinate, so in this sense it is presentationally "thick". In a way, the experience itself serves as its own mode of presentation in this case, for if it were not present the relevant concept could not be formed. This is what is meant by the term "substantive". To say that a mode of presentation is determinate, means that it presents certain and specific quality in its own right. In the case of "thick" modes of presentation cognitive significance is more relevant for the content of a concept than the information about the relation of a property it represents with 28 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 29 30 Daniel Kostić other properties. Having distinguished "thin" and "thick" modes of presentation we can say now that phenomenal concepts are "thick" concepts because they rely on the "thick" modes of presentation. On the other hand, natural kind concepts are "thin" concepts because they are based on the "thin" modes of presentation. That is, our cognitive access to the representation of a situation is not in any significant way tied to the experience of that situation. On the other hand, in the case of psychophysical identity our cognitive access to the phenomenal side plays a significant part of the concept of experience. In this case we have a "thick" concept. The difference between thick and thin concepts in Levine's account comes down to this: the semantics of the thick concepts is determined by modes of presentation wherein a state or a quality presents itself regardless of the nomic relations a given property might have with other properties. In other words, one could have a thick concept of experience without knowing anything about the nomic or causal relations of the property it picks out with other properties. On the other hand, one could have a thin concept without having the determinate and substantial cognitive access to the content of a thin concept. This situation plays an essential role in the conceivability arguments as well. What is meant by the claim that the physicalist explanation leaves out something is that the two ways in which thin and thick concepts are determined seem incompatible. Natural kind concepts/thin concepts are based on the descriptions of the causal or nomic roles their referents play, whereas phenomenal/thick concepts are based on the immediate and determinate quality of experience that in a sense presents itself. Why should this be a problem? Levine holds that the problem lies in the fact that one of the plausible explanations could be that these two ways in which we pick out properties reflect the metaphysical gap between the phenomenal and the physical properties. On the other hand, given that we have very good reasons to believe that materialism is true based on the causal argument (Papineau 2002), the incompatibility of thick and thin concepts render the psychophysical identity unintelligible even if it were true. We will come to this point very soon. Let's continue with laying out Levine's account. 2. Ascriptive and non-ascriptive modes of presentation and apriority and necessity Our next issues are the modal and epistemological aspects of the explanatory gap problem. Levine's idea about the relation between these two notions can best be articulated through his analysis of the conceivability arguments. Starting off with the terminological clarifications about what is meant by "metaphysically possible" or "logically possible", Levine (Levine 2001, p. 40) The Explanatory Gap Account and Intelligibility of Explanation 29 30 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 31 argues that there is no real distinction between them. For him the logically possible is metaphysically possible, or just plainly possible. Instead of that he introduces the distinction between logically/metaphysically possible and conceptually possible. The crucial distinction here is between "situations" and our modal judgments about them. The modal status of a "situation" is mind independent, that is to say they could be metaphysically possible without us knowing about it. On the other hand, when a "situation's" modal status is dependent on our judgements then it is conceptually possible. This point will come very handy later on in presenting Levine's account of what follows from the conceivability arguments. Suffice it say that it obviously follows from these considerations that a "situation" cannot be metaphysically necessary without being conceptually necessary. A very important distinction here is what Levine takes the connection between the epistemological and metaphysical sides of modality to be. These distinctions are based on the dependency of our modal judgements upon our epistemic situation. For example, someone could be in a position to judge it as necessary that H2O contains hydrogen and that water contains hydrogen. But someone else who is ignorant of the chemical composition of water would not judge it as necessary, because that person would not know the relevant description of the causal roles under which both "water" and "H2O" pick out the same thing, that is she would be unaware of the bridging claim that "water=H2O". That is to say, our judgements about factual and modal descriptions of the situations are relative to the representations that we use to pick those situations out. Naturally, a "situation" in this context is taken to mean "an object instantiating one or more properties or an ordered n-tuple of objects that serve as the truth conditions for a statement" (Levine 2001, p. 40), that is, a "situation" allows us to evaluate a statement as true or false. Now comes an important part of the argumentation. It is the relation between conceptual possibility and metaphysical possibility. A situation S, is conceptually possible, iff when thought of under the representation R, it is possible. On the other hand, a situation S' is metaphysically possible iff S' is conceptually possible under representation R and it is not a priori that not-R (Levine 2001, p. 40). A simple principle then follows, if there is a description of a situation according to which the situation is conceptually impossible, then it is metaphysically impossible (Levine 2001, p. 46). Let me clarify a very important point about a priority and necessity in this context. Consider a statement "Water contains hydrogen". To render this statement necessary, three crucial requirements must be met. First, that the statement "H2O contains hydrogen" is a priori, i.e. that its truth or falsity can be evaluated solely on the ground of the meaning of the terms involved. Second, that there is an empirically discoverable fact, thus a posteriori, that water is H2O. Finally, the third requirement is that the statement picks out a situation in which water contains H2O. Based 30 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 31 32 Daniel Kostić on these preliminaries we evaluate a statement as necessary even if it is a posteriori. That is, to render an a posteriori statement necessary, there has to be an a priori description from which that statement can be derived. This is so at least in the case of natural kinds. In a sense each statement that is metaphysically necessary must be also conceptually necessary, and if a statement is conceptually impossible it is metaphysically impossible. Thus far this seems obvious. On the other hand, a statement that is metaphysically impossible is not necessarily conceptually impossible as we have seen in the case of water/H2O. That is to say, if a situation is conceptually possible that fact alone does not justify entailment to metaphysical possibility. Basically, this point follows from the claim that the only way we can evaluate a situation's modal status is through a representation of the given situation. In Levine's view (Levine 2001, p. 46), the fact that conceptual possibility does not entail metaphysical possibility is exemplified by all cases of a posteriori necessity. If physicalism were true it should also fall in this category. So how does this account relate to conceptual and metaphysical necessity? Basically, this account comes down to two-dimensional semantics. What is conceptually possible is in Chalmers's lingo 1-possible and what is metaphysically possible is 2-possible. What happens in Levine's analysis of the conceivability arguments is not much different from the two-dimensional analysis, at least in terms of basic conceptual assumptions. The point where Levine departs from the standard interpretation of the conceivability arguments is with the epistemic assumptions. Namely, Levine claims that unlike the identities of natural kinds, wherein our epistemic situation is "thin", in the case of phenomenal concepts our epistemic situation is "thick" which makes the psychophysical identity a gappy identity. I will explain what a "gappy" identity is in a moment. Before that I just need to crudely elaborate on Levine's departure from the standard interpretation of the conceivability arguments. If the "thick" concepts are not based on the modes of presentation that involve nomic or causal relations between properties, then it is possible in principle that a characterization of a counterfactual situation containing "thick" concepts might be missing some relevant description, i.e. a description that could render the counterfactual situation metaphysically impossible. This in fact leads only to the conceptual possibility of zombies. Because the "thick" concepts are flanking on the one side of the psychophysical identity, that kind of identity is "gappy". It is very interesting to note that the very same assumption about the phenomenal concepts that supports the metaphysical and anti-materialist conclusions of the conceivability arguments is employed here to block the inference to metaphysical possibility. Another way of explicating this view is through the analysis of the modes of presentation. Namely, Levine (Levine 2001, p. 54) distinguishes between ascriptive The Explanatory Gap Account and Intelligibility of Explanation 31 32 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 33 and non-ascriptive modes of presentation. Ascriptive modes of presentation are those we are already familiar with from Kripke and Chalmers's versions of the conceivability argument. According to ascriptivists the concepts pick out their referents via the descriptions of their standard causal or functional roles. The point that clearly distinguishes between ascriptivists and non-ascriptivists is that whereas ascriptivist believes that the a priori knowledge is a matter of having enough information about the causal or functional roles properties normally play, a nonascriptivist maintains that a priori knowledge cannot be founded in such a way. On the other hand, the non-ascriptive mode of presentation works in such a way that the content of a concept is determined by the formal relations a given property has with other properties. 3. Thick and thin conceivability Let's turn our attention now to rather technical aspects of the explanatory gap account. The claim that the conceivability argument only establishes an epistemic possibility of counterfactual scenarios has been a subject of many vigorous debates over the years2. For the purpose of this paper and sake of brevity we won't go into details of these debates. However the argument that separates the epistemic possibility from the metaphysical one needs to be rehearsed. This issue is of central importance to the explanatory gap account and now we will consider it in some detail. We have seen in the contrasting cases of natural kind identities that the conceivability argument breaks down when it comes to the entailment from conceivability to possibility and that it goes right through in the qualia case. According to Levine's interpretation of the argument, it is so because metaphysical possibility relies upon conceptual possibility. Namely, we get to the metaphysical possibility not directly from conceivability but through conceptual possibility first. The notion of conceptual possibility only requires that a counterfactual situation that we are conceiving of should not be inconsistently inferable from the situation we start with. If a situation is conceptually possible, it is metaphysically possible as well (Levine 1998, p. 454). Since there is no inconsistency in conceiving of a situation "brain state B but not quale M" it is then conceptually possible that "brain state B but not quale M", and if this is conceptually possible then it is metaphysically possible. This is the standard "metaphysical reading" of the explanatory gap according to Levine. What he needs now is a move that undermines the inferential link between conceptual and metaphysical possibility, thus establishing only epistemic possibility of counterfactual cases of qualia. 2 Cf. (Chalmers & Jackson 2001), (Block & Stalnaker 1999), (Stoljar 2000, 2001), (Levine 1998, 2001), (Balog 1999), (Hill 1997), etc. 32 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 33 34 Daniel Kostić Levine argues that there could be two ways to understand the inferential link, by analyzing the ways concepts connect to their referents, or the concept's modes of presentation (Levine 1998, pp. 457-8). On the one hand they could involve ascriptive modes of presentation and on the other non-ascriptive modes of presentation (Levine 1998, 2001). Ascriptive modes of presentation are, normally, involved in standard cases of natural kind identity, wherein we have two distinct concepts that pick out the same thing. This case involves ascription of properties to the referent by way of instantiating the properties that are referred to; for example, the causal roles of water. The non-ascriptive mode of presentation uses other methods. The crucial difference between the two is that in the case of ascriptive mode the properties are only contingently related to each other. Whereas in the case of the non-ascriptive mode properties are related in some other way and not necessarily cognitively represented. According to Levine, we only need non-ascriptive modes of presentation to undermine the link between conceptual possibility and metaphysical possibility in the case of zombies (Levine 1998, 2001), because if they are nonascriptive then we cannot know whether something is missing from the zombie description and therefore allowing for the inconsistent description of zombies. In other words, non-ascriptive modes of presentation undermine the inference from conceptual possibility to metaphysical possibility. To see more clearly how this blocking works let's consider it in terms of conceivability. Levine distinguishes two grades of conceivability: thin and thick conceivability (Levine 1998, p. 468; 2001). A thinly conceivable situation is based on a plain conceptual possibility, i.e. a situation is thinly conceivable iff it is not inconsistent to infer it from the actual situation. On the other hand, a situation is thickly conceivable if it is conceptually possible and if any inference from its conceptual possibility to metaphysical possibility is based on gappy identities3. In this way the link between conceivability and metaphysical possibility is undermined. This view is unfortunate for the materialists because it implies that the only way to defend materialism is by conceding on the gappy psychophysical identity. On the other hand, to say that a situation is epistemically possible is to say that there is nothing in our knowledge that would make it metaphysically impossible. 4. Gappy and non-gappy identities The point of gappy and non-gappy identities comes down to this: gappy identities require some explanation of how these two concepts pick out the same property. Non-gappy identities imply distinct properties. If zombies are conceivable 3 I will explain this notion in the next section. The Explanatory Gap Account and Intelligibility of Explanation 33 34 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 35 then it is so because either psychophysical identity is a gappy identity or there is no identity after all. Now how does this stop the flow from conceptual possibility to metaphysical possibility? In the natural kinds cases a situation can be conceptually possible but metaphysically impossible nevertheless. If we want to break the inference from conceptual possibility to metaphysical possibility in the case of qualia, we need to use gappy identities and claim that proper identities need no explanation of their truthfulness. However, it is because of this manoeuvre that we need a further explanation of how the two distinct concepts pick out the same property. This is what is meant by the claim that the explanatory gap saves materialism from the metaphysical consequences of conceivability arguments but at the price of the explanatory gap. Levine claims that there are two main aspects of the explanatory gap. One involving incompatibility of thick and thin concepts and the other involving gappiness of the psychophysical identity, which is based on the intelligibility of the further request for an explanation. My idea is that gappiness in Levine's case is actually based on the idea of incompatibility of thick and thin concepts which in effect dissolves very easily when we realise that the intelligibility of explanation need not stem directly from the identity. Thus this account only succeeds in establishing the epistemic gap-a merely descriptive gap between two semantically distinct concepts. 5. Intelligibility of explanations The explanatory gap account is supposed to show that the metaphysical conclusions standardly drawn from the conceivability arguments do not hold but at the price of the explanatory gap. To elaborate on this point Levine (Levine 2001) distinguishes between two aspects of an explanation: the metaphysical explanation, according to which we explain property A in virtue of property B, and an epistemological explanation, which is supposed to explain why property A is explicable in virtue of property B. In another words, epistemological explanation makes it intelligible why given B there is A. They are of course interconnected and interdependent, but it is crucial to note that they are not the same thing. For example, if one were to try explaining my visual experience of a red tomato metaphysically, the explanation would appeal to the fact that at certain point in time t, when I had an experience S, my brain was occupying a state B at t. However, to make this explanation intelligible we need a theory of realization that would tell us how B realizes A, according to Levine. There is another aspect of the explanatory gap, which concerns mainly the issue of explanations and identities. Take, for example, our contrasting cases of natural kinds and phenomenal kinds. Levine (Levine 2001, 2007) agrees that proper 34 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 35 36 Daniel Kostić identities need no additional or further explanations. If being in a brain state B were the same as having a "reddish" quale Q, then it doesn't make much sense to ask what makes this identity statement true. However, it is legitimate to ask why given brain state B there is the quale Q. In the case of natural kinds an answer to this question can take only two routes according to Levine (Levine 2001, p. 81). One way to explain it is by relying on the basic or fundamental law; the other way is through the identity premise itself. Let's turn our attention now to the issue of explanation in the explanatory gap and try to connect the notions elaborated above. Levine (Levine 1983, p. 357) argues that even if we succeeded in explaining the causal or functional roles of qualia, there is still the qualitative character of our sensory experiences that is left out by this sort of explanation. For a property to be left out from a theory mean that the theory cannot refer to these properties (Levine 1993, p. 121). Unlike cases of identities of natural kinds, like water and H2O or heat and molecular motions, wherein a requirement for further explanation does not seem intelligible, because the seeming contingency can be explained away by either deriving the identity from more fundamental statements or dismissed as a misdescription, in the case of qualia this requirement does make very much sense. Levine (1999) holds that most of the natural kind identities are not self-evidently explicable either, and that we can legitimately ask for further explanation. However, after providing the descriptions from which the natural kinds flanking the identity statement are derived, we come to realize that the request for further explanation is just a request for a justification. On the other hand, in the qualia case no derivation seems possible and the puzzlement about how qualia and brain processes could be identical deepens even more as we add refinement to our concepts of qualia or of brain processes. Levine holds that it is so because the psychophysical identity is a "gappy identity" (Levine 1998, 1999, 2001). A gappy identity is an identity statement which makes it intelligible to request for further explanation. Of course, non-gappy identity is the one for which it is not intelligible to require further explanation. To illustrate this point let's compare two patterns of explanation. One involving the boiling point of water and the other involving the presence of the reddish quale. Let's start with the boiling point of water: I."H2O molecules exert vapor pressure P at kinetic energy E; II. At sea level exerting vapor pressure P causes molecules to rapidly escape into air; III. Rapidly escaping into air is boiling; IV. 100°C is kinetic energy E; V. Water is H2O; VI. Water boils at 100°C at sea level." (Levine 1999, p.4) The Explanatory Gap Account and Intelligibility of Explanation 35 36 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 37 This is clearly the case of a non-gappy identity according to Levine. One can legitimately ask why V. is true, but once we provide enough details of the causal roles of water, or we fill in the microphysical description of the behaviour of water, it seizes to make sense to ask for further explanation. In a sense, scheme of the causal roles of water and sufficiently refined microphysical description exhaust all there is about an explanation of the natural kinds identity. We are not left with a sense that something is missing. It is, however, crucial to note that in this example V. serves as a binding point for the reference of water and H2O in the explanation. It identifies the phenomenon to be explained with a phenomenon that is describable in terms of microphysics. It enables V. to be derivable from the combination of statements that are either a priori or are descriptions of the underlying microphysical phenomena, which in effect makes it unintelligible to ask for further explanation of V.'s truth. Furthermore, if we try to abstract the formal structure of the derivation, it comes down to this: VII. "Water is the stuff that manifests the "watery" properties; VIII. H2O manifests "watery" properties; IX. Water is H2O." (Levine 1999, p. 5) It is important to note that premise VII. is analytic and that the characterization of properties in question is given in "topic neutral" terms. To say that premise 26. is analytic in this context means that one can know it is true solely on the ground of knowing what the terms involved mean. "Topic neutral" here means simply that the terms that pick out properties in question do not contain any vocabulary that is not contained in the theory that does the explaining. These two features of the binding premise are crucial for the derivation, because ultimately, the explaining of the identity must end up either with the fundamental law or it has to be derived from the identity premise itself, otherwise it would not be an explanation at all. Let's now consider the case of reddish quale. X. "S occupies brain state B; XI. Occupying brain state B is to experience a reddish quale; XII. S is experiencing a reddish quale." (Ibid) In this case we have a gappy identity. Regardless of the amount of detail that we could stack in between X. and XI. it still makes sense to ask why is XI. true. It is because of the nature of the binding premise XI. As we have seen, premise VII. enables the macro phenomenon to refer to the microphysical descriptions or to the combination of analytic statements. Premise XI., however, considered as a binding premise, the premise that is supposed to identify the phenomenon that is to be explained with the microphysical description or with a combination of analytic 36 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 37 38 Daniel Kostić statements, is not derivable from the combinations of analytic definitions. Let's have a look at what would formal structure of the derivation look like in this case. XIII. "Qualitative state R is the state that plays causal role C; XIV. Brain state B plays causal role C; XV. Brain state B is qualitative state R. (Levine 1999, p. 6) Here, the premise XIII. should be analytic for the derivation to work. However, it is not analytic, although it may be that some qualitative states play certain causal or functional roles, but even if they do it is not the conceptual truth. In Levine's terms the premise XIII. that is supposed to be a binding premise is actually an example of a gappy identity. It is in fact in need of further explanation. It just seems coherently conceivable that there could be a conscious experience that does not play the typical causal or functional role for the related state. No other corroboration for the assumptions is provided. We have come to the crucial point of the account. Given that it is coherently conceivable that qualia could not play their typical causal or functional roles, this only shows that the claims about their typical causal or functional roles are not analytic, which suffices only for establishing the explanatory gap. The conceivability argument itself does not demonstrate the metaphysical possibility of causal or functional dissociations. To establish metaphysical possibility in the conceivability argument a new argument would be required. Now it becomes clearer what it means for the physicalist explanation of phenomenal consciousness to leave out something. Namely, physical-empirical explanations are supposed to use "thin" concepts whose semantics is based on the modes of presentation that bear very little on the cognitive significance in picking out their referents. On the other hand phenomenal concepts almost entirely depend on the "thick" modes of presentation, wherein a property basically presents itself and the mode of presentation is almost exhausted in the cognitive significance. "Thin" concepts leave out the content of "thick" concepts. More importantly, "thin" concepts cannot include the content of "thick" concepts in principle. Why should this be a problem? Well, that is exactly Levine's point. This situation does not create a metaphysical problem because it is perfectly reasonable that the same property can be picked out in two different ways. For example, we can conceptualize our experiences in terms of the causal roles brain states or properties normally play and, on the other hand, in terms of picking out their immediate qualities. However, claims Levine, this creates an epistemological problem because why the content of a particular "thick" concept is as it is not intelligible, given the content of a respective "thin" concept and also given that both concepts pick out the same thing. Furthermore, exactly because of the relation between the "thick" and the "thin" concepts, the conceivability arguments fail to establish the metaphysical possibility of counterfactual causal, supervenience The Explanatory Gap Account and Intelligibility of Explanation 37 38 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 39 dissociations or causal or functional inversions. This according to Levine is the price physicalists have to pay if they were to avoid the metaphysical consequences of the conceivability arguments. However, why would physicalists concede on this rather high price for the truth of physicalism? Levine claims that fully intelligible/non-gappy explanation of the psychophysical identity ought to rely on what he calls ascriptive modes of presentation. Given that phenomenal concepts, or as he calls them thick concepts, use nonascriptive modes of presentation, the psychophysical identity is rendered a gappy identity and thus cannot be fully intelligible. But this intelligibility requirement is not justified. It rather rests on a presupposition that intelligible explanation of the psychophysical identity must come from the conceptual analysis alone. In another words, an explanation ought to identify explanans and explanandum via a scheme of descriptions of the causal or functional roles in order to be fully explanatory. That is to say, it needs to include a two step approach which consists of working out a scheme of causal or functional roles and then finding the role fillers. Some philosophers, such as Chalmers (Chalmers 1996, 2009), and Chalmers and Jackson (Chalmers and Jackson 2000) maintain that these two steps should even a priori follow from the complete physical information. However, if this sort of analysis is available for the natural kinds identities it is not clear why a mere existence of the epistemic gap would be an obstacle for such analysis in the case of the psychophysical identity. This view rests on the assumption that ascriptive modes of presentation, that use descriptions of causal or functional roles, actually imply a difference in properties. Ned Block calls it metaphysical modes of presentation as opposed to cognitive modes of presentation. However, my point here is that we could have a true identity that involves thick and thin concepts which are based on distinct cognitive modes of presentation rather than on metaphysical modes presentation (which would in fact imply a metaphysical difference in properties). This is a recurring objection in philosophy of mind, that began with the anecdotal account of the remark Max Black gave to J.J.C. Smart (Smart 1959). Basically Max Black objected that if one is to postulate an identity between the phenomenal and the physical then the concepts flanking the identity sign that deploy independent modes of presentation are based on distinct properties in virtue of which these modes of presentation differ. What seems to be the problem here is that phenomenal concept needs to have a phenomenal mode of presentation which ought not be physical, that is, it should not be the property itself. Levine seems to be claiming this as well. Nevertheless, as Ned Block (Block 2007) has powerfully argued, distinct concepts flanking the identity sign need not be based on metaphysically distinct properties. The view that they do rests on an assumption that necessary, a difference in cognitive modes of presentation entails a difference in metaphysical modes of presentation. This shouldn't be the case according to Block. 38 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 39 40 Daniel Kostić Cognitive modes of presentation do not necessary entail metaphysical modes of presentation. He presents a scenario which corroborates this claim. Imagine there was a student who wanted to learn French. He is an absolute beginner. One day his teacher shows him a cat and says that a French word for cat is "chat". Later on the same day the absentminded teacher shows the same cat to the student and again introduces the "chat" for cat. The student thinks it is a different cat and he associates the first appearance of cat with a concept "chat1" and second appearance with "chat2". He sincerely believes there is a metaphysical defence between two appearances of the cat. But we see from this example that there was only one cat and the student acquired the concept "chat" under two cognitively distinct modes of presentation. In this case the difference in cognitive modes of presentation did not entail a difference in metaphysical modes of presentation. This proves that the entailment from cognitive to metaphysical modes of presentation is not necessary and furthermore this explanation makes psychophysical identity fully intelligible. The other problem with the explanatory gap account is that it rests on an assumption that fully intelligible explanations must be based only on the conceptual analysis. This requirement is not justified either. As it was established earlier, we could think about consciousness from the first and from the third person perspective, i.e. we can use thick or thin concepts of our experience and have an independent account of its intelligibility, because as we saw, identities are not explanatory to begin with. In conclusion, the explanatory gap account only succeeds in establishing the epistemic gap. The claim that psychophysical identity is not completely intelligibly explicable, and thus opens the explanatory gap, would require an independent argument which would prove that intelligible explanations stem only from conceptual analysis. This, as we have seen, is not the case, even with the natural kinds. Identities are not explanatory in themselves. Their purpose is to transfer causal or explanatory force onto the other properties. However, if one finds the epistemic gap baffling, one ought not to infer the explanatory gap directly from it. Intelligibility of the psychophysical identity should not be sought in the conceptual analysis, but elsewhere. I suggest looking into the workings of psychological concepts of phenomenal consciousness and study why would one expect that phenomenal concepts/thick concepts should be based on the descriptions of the causal/functional roles in order to be fully explanatory. Daniel Kostić Berlin School of Mind and Brain Humboldt-Universität zu Berlin The Explanatory Gap Account and Intelligibility of Explanation 39 40 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 41 Literatura Block, N. and Stalnaker, R.,1999. "Conceptual Analysis, Dualism, and the Explanatory Gap". Philosophical Review, 108, (1), pp. 1-46. Block, N.,2007. "Max Black's Objection to Mind-Body Identity". In: Alter, T. and Walter, S. eds., 2007. Phenomenal Concepts and Phenomenal Knowledge: New Essays on Consciousness and Physicalism. Oxford: Oxford University Press. Chalmers, D.,1996. "The Conscious Mind". New York: Oxford University Press. Chalmers, D. and Jackson, J., 2001. "Conceptual Analysis and Reductive Explanation". Philosophical Review, 110, pp. 315-360. Chalmers, D., 2002a. "Does Conceivability entail Possibility". In: Gendler T. S. and Hawthorne, J.,eds. Conceivability and Possibility. Oxford: Oxford University Press. Chalmers, D.,2009. "The Two-Dimensional Argument Against Materialism". In: McLaughlin B. P. and Walter S., eds., 2009. Oxford Handbook to the Philosophy of Mind. Oxford: Oxford University Press. Davies, M. and Humberstone, I. L.,1980. "Two Notions of Necessity". Philosophical Studies, 38, pp. 1-30. Hardin, L. C.,1987. "Qualia and Materialism: Closing the Explanatory Gap". Philosophy and Phenomenological Research, 48, pp. 281-298. Harman, G.,1990. "The Intrinsic Quality of Experience". Philosophical Perspectives 4, pp.31-52. Hill, C. S.,1997. "Imaginability, Conceivability, Possibility, and the Mind-Body Problem". Philosophical Studies, 87 (1), pp. 61–85. Hill, C. and McLaughlin, B., 1999. "There Are Fewer Things in Reality that Are Dreamt of in Chalmers' Philosophy". Philosophy and Phenomenological Research, 59, pp. 445-454. Jackson, F.,1982. "Epiphenomenal Qualia", Philosophical Quarterly, 32 (127), pp. 127-136. Jackson, F.,1986. "What Mary Didn't Know". Journal of Philosophy, 83 (5), pp. 291-295. Jackson, F.,1998a. "From Metaphysics to Ethics: A Defence of Conceptual Analysis". New York: Oxford University Press. Kripke, S.,1980. "Naming and Necessity". Cambridge Massachusetts: Harvard University Press. Levine, J.,1983. "Materialism and Qualia: The Explanatory Gap". Pacific Philosophical Quarterly, 64, pp. 354-361. Levine, J.,1993. "On Leaving Out What It's Like". In: Davies M. and Humphreys G., eds., 1993. Consciousness: Psychological and Philosophical Essays, Oxford: Blackwell. Levine, J.,1998. "Conceivability and the metaphysics of mind". Nous, 32(4), pp. 449-480. Levine, J.,1999. "Conceivability, Identity, and the Explanatory Gap". In: Hameroff, S. R. and Chalmers, D.J. eds., 1999. Toward a Science of Consciousness III: The Third Tucson Discussions and Debates. Cambridge, MA: MIT Press. Levine, J.,2001. "Purple Haze: The Puzzle of Conscious Experience". Cambridge, MA: MIT Press. Loar, B.,1990. "Phenomenal States". Philosophical Perspectives, 4, pp. 81-108. Loar, B.,1997. "Phenomenal States (Revised Edition)". In: N. Block, O. Flanagan and G. Güzeldere . eds., 1997. The Nature of Consciousness: Philosophical Debates. Cambridge, MA: MIT Press. 40 Daniel Kostić The Explanatory Gap Account and Intelligibility of Explanation 41 42 Daniel Kostić Nagel, T.,1974. "What is it Like to Be a Bat?" Philosophical Review, 83 (4), pp. 435-450. Nagel, T.,1979. "Subjective and objective". In: Nagel, T.,1979. Mortal Questions. Cambridge: Cambridge University Press. Papineau, D.,1993. "Physicalism, consciousness and the antipathetic fallacy". Australasian Journal of Philosophy, 71, pp.169–183. Papineau, D.,1998. "Mind the gap". Philosophical Perspectives, 12, pp. 373-88. Papineau, D.,2002. "Thinking about Consciousness". Oxford: Oxford University Press. Papineau, D.,2007. "Phenomenal and Perceptual Concepts". In: Alter T. and Walter S.,eds., 2007. Phenomenal Concepts and Phenomenal Knowledge: New Essays on Consciousness and Physicalism. Oxford: Oxford University Press. Place, U. T.,1956. "Is Consciousness a Brain Process?" British Journal of Psychology, 47, pp. 44-50. Putnam, H.,1967. "Psychological Predicates". In: Capitan W. H. and Merrill D. D., eds. Art, Mind and Religion. Pittsburgh: University of Pittsburgh Press. Smart, J. J. C.,1959. "Sensations and Brain Processes". Philosophical Review, 68, pp. 141-156. Sturgeon, S.,1994. "The epistemic basis of subjectivity". Journal of Philosophy, 91, pp. 221-35. Stoljar, D.,2000. "Physicalism and the Necessary a Posteriori". The Journal of Philosophy, 97 (1), pp. 33-54. Stoljar, D.,2001. "Two Conceptions of the Physical". Philosophy and Phenomenological Research, 62, pp. 253-281. Stoljar, D.,2005. "Physicalism and Phenomenal Concepts". Mind and Language, 20, pp. 469-494. Tye, M.,1999. "Phenomenal Consciousness: the Explanatory Gap as a Cognitive Illusion". Mind, 108, pp. 705-725. Tye, M., 2003. "A theory of phenomenal concepts". In: O'Hear A.,ed., 2003. Minds and Persons. Cambridge: Cambridge University Press. Daniel Kostić Tumačenje objašnjavalačkog jaza i razumljivost objašnjenja (Apstrakt) Ovaj tekst se bavi tumačenjem objašnjavalačkog jaza, analizirajući ključne pojmove za njeno razumevanje. Analiza se posebno bavi ulogom "thick" i "thin" ("punih" i "tankih") modova prezentacije i "thick" i "thin" pojmova koji su bitni za razumevanje "thick" i "thin" tipove zamislivosti, i samim tim bitni za "gappy" i "ne-gappy" identitete. Konačno, u poslednjem delu ovog teksta ispituje se problem razumljivosti objašnjenja. Jedan od The Explanatory Gap Account and Intelligibility of Explanation 41 42 Daniel Kostić zaključaka je da teorija objašnjavalačkog jaza uspeva da dokaže samo epistemički jaz. Tvrdnja da psihofizički identitet nije razumljivo objašnjiv, čime se otvara objašnjavalački jaz, zahtevala bi nezavisan argument koji bi dokazao da razumljiva objašnjenja proizlaze isključivo iz pojmovne analize. Ja dokazujem da ovo nije slučaj. KLJUČNE REČI: Objašnjavalački jaz, epistemički jaz, modovi prezentacije, zamislivost, mogućnost, razumljivost objašnjenja.