Searle’s Ontology of the Mind in the Universe: a criticism
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- 1. The Existence of Conscious Minds
- 2. The Mental as a Physical Phenomenon
- 2.1 Failing Analogy: the Mental as a Macro-feature of a Physical Micro-system
- 2.2. Irreducibility of the Mental Matters
- 2.3. Nagel’s Argument for Causal Irreducibility
- 3. Conclusion
Searle’s Ontology of the Mind in the Universe: A Criticism (Daniel D. Novotny, UB Spring 2002, second version) In its general outline Searle’s ontology can be summarized as follows: all things that exist are physical but some of them also mental. This view is a conjunction of two propositions, (a) all things are physical, and (b) some things are mental. Needless to say, many philosophers consider (a) and (b) to be inconsistent. Dualists, for instance, accept (b) and for that reason reject (a), materialists conversely reject (b) for the sake of accepting (a). Both dualists and materialists, however, assume that one cannot hold both (a) and (b)1. More specifically Searle holds that (a) every existing thing consists entirely of physical particles in fields of force (physicalism), and (b) some things are endowed by conscious and subjective minds (mentalism). Since Searle takes (a) for granted and assumes that “any reasonably educated citizen of the present era” does as well2, his attention is directed toward defending (b) and especially the compatibility of (b) with (a). In my paper, I shall accordingly evaluate first Searle’s discussion of (b) and then his arguments for the compatibility of (b) with (a). With respect to (b) I agree with Searle that the mind with its properties such as consciousness and subjectivity is something which cannot be dismissed or denied and which has to be accounted for in any adequate and complete ontological theory. With respect to Searle’s discussion of the compatibility of (b) and (a), however, I shall argue that it is in at least three important respects wanting. First, I criticize Searle’s view that the analogy between solidity and consciousness as a macro-feature of a micro-system satisfactorily illuminates the unproblematic character of the mental in the physical world. Second, I argue that Searle’s defense of the ontological irreducibility of consciousness is terminologically confused and that his complex argument for the trivial nature of that irreducibility is unsuccessful. Third, I defend Nagel’s argument for causal irreducibility of conscious minds by answering some of Searle’s objections to it. Needless to say, causal irreducibility of mind threatens one of the fundamental aspects of Searle’s ontology, namely its thoroughgoing physicalism. 1. The Existence of Conscious MindsThe sentence ‘some things that exist are mental’ is so vague that in one way or another every philosopher would agree with it. Searle, however, understands by it a specific fact, namely that each of us, human persons, finds himself in various conscious states which constitute, metaphorically speaking, his subjective “inner realm”. Although there is more than one legitimate way to characterize the mental - being subjective, having intentionality etc. - it is consciousness which is in Searle’s view the most fundamental characteristic of mentality. One may say that for Searle being conscious is the sole necessary and sufficient condition for an X to be appropriately called “mind”. Searle’s characterization of consciousness is with some qualification basically identical to Descartes’ characterization of thought (though their answers with respect to its ontological status radically differ). For an illustration we may compare two passages, one from Searle’s and one from Descartes’ works:
Searle: “By consciousness I do not mean the passive subjectivity [sic!] of the Cartesian tradition, but all of the forms of our conscious life---from the famous “four f’s” of fighting, fleeing, feeding, and fornicating to driving cars, writing books, and scratching our itches. All of the processes that we think of as especially mental—whether perception, learning, inference, decision making, problem solving, the emotions, etc.—are in one way or another crucially related to consciousness.” (Searle 1992: 22) Descartes: “By the word ‘thought’ I understand all those things which occur in us while we are conscious, insofar as the consciousness of them is in us. And so not only understanding, willing and imagining, but also sensing, are here the same as thinking.”3 (Descartes 1983: 5) The existence of consciousness in the above-indicated sense would to an ordinary man from the street hardly ever be considered dubitable. From one’s own experience it is obvious that conscious minds exist. Surprisingly, however, in various ways, the majority of contemporary philosophers of mind (at least according to Searle’s assessment of the situation) bypass or even deny the mind’s existence - implicitly or explicitly, simply or in a sophisticated manner. In fact, to vindicate the reality of consciousness was one of Searle’s primary motives for writing the book The Rediscovery of Mind4. To offer some arguments against those who deny the existence of something so obvious as conscious minds is not an easy and straightforward task. What one can do, at best, is to try to “break the hold” of the false picture which precludes seeing obvious truth. One of the ways Searle follows is the “Silicon Brain” thought experiment (1992: 65-70): There is a patient, let us name him John, which has a disease causing a progressive deterioration of the brain. Luckily, medicine is already so developed that the damaged parts of John’s brain can be replaced by silicon chips. Conceivably, argues Searle, there are three possible outcomes of the medical procedure: First, John is unaware of any change in his conscious life and the doctors do not register any difficulties in John’s mental life. Second, John feels that the range of his conscious activities is gradually shrinking so that it eventually disappears. At the same time, however, his overt behavior remains unaltered. Third, John is perfectly conscious but it is impossible for him to communicate with the environment - eventually, from the doctor’s point of view, John is brain-dead (totally non-responsive). The eventual results of the experiment/procedure are to be interpreted as follows: In the first case the silicon chips would do the same job as the brain processes, i.e. they would be the cause of both the conscious life and the appropriate externally observable behavior. In the second case the silicon chips would be the cause only of the appropriate externally observable behavior but not of the conscious life. In the third case the silicon chips would cause only the conscious life but not the externally observable behavior. Now, there are at least two lessons one can learn from this thought experiment. First, the experiment undermines the logical interdependence between the consciousness and the outer behavior. This fact has serious consequences for those who identify the two (or rather substitute the overt behavior for Descartes-Searle’s consciousness). Second, we see we need to make a distinction between the first-person perspective of the patient and the third-person perspective of the doctors. This distinction indicates that besides the “outer”, objective world, there also exist minds with their “inner”, conscious and subjective side. Consequently, argues Searle, any adequate and complete ontological theory must acknowledge the existence of conscious minds and account for both objective (non-mental) and subjective (mental) forms of reality.
2. The Mental as a Physical PhenomenonAs I have already said, the claim (b) some things are endowed with conscious (i.e. subjective) minds leads dualists to abandon (a) every existing thing consists entirely of physical particles in fields of force. For Searle, however, both claims are compatible and true since the mental is a form of the physical. Searle writes, When I say that consciousness is a higher-level physical feature of the brain, the temptation is to hear that as meaning physical-as-opposed-to-mental, as meaning that consciousness should be described only in objective behavioral or neurophysiological terms. But what I really mean is consciousness qua consciousness, qua mental, qua subjective, qua qualitative is physical, and physical because mental. (Searle 1992: 15) Searle calls his view “biological naturalism”. “Naturalism” since the nature (described by physics) is ontologically the primary reality, “biological” since, [c]onsciousness, in short, is a biological feature of human and certain animal brains. It is caused by neurobiological processes and is as much a part of the natural biological order as any other biological features such as photosynthesis, digestion, or mitosis. (1992: 90) Biological naturalism is a very appealing position for it does justice both to the generally widespread understanding of the knowledge gained by natural sciences and to the common life intuitions about our mental lives. Moreover, it seems to dissolve elegantly the notorious body-mind problem as it has been inherited from Descartes. Searle’s defense of biological naturalism is complex and rhetorically suggestive. In what follows I would like to focus on three crucial elements of it. The cumulative result of my criticisms is to show the overall implausibility and inconsistency of it. First, I criticize Searle’s contention that the mental is a macro-feature of a physical micro-system similarly as solidity and photosynthesis are. Second, I argue against Searle’s thesis that ontological irreducibility of consciousness is a trivial matter. Third, I defend Nagel’s argument for causal irreducibility of conscious minds, which goes against the basic tenets of Searle’s ontology. 2.1 Failing Analogy: the Mental as a Macro-feature of a Physical Micro-systemApparently, the crucial point of Searle’s ontology is to account for how there can be minds characterized by consciousness and subjectivity (i.e. accessible only from the first-person perspective) in the world consisting entirely of non-conscious and objective particles and fields of force. Searle believes that in principle the answer is rather easy: subjectivity, along with solidity, liquidity, digestion etc., is a macro-feature of a micro-system. And similarly, argues Searle, as it is inappropriate to wonder how there can be liquid things in a world of non-liquid micro-particles, or digestion in a world of chemicals, which do not digest, it is inappropriate to be puzzled by the subjective and conscious minds in the world of objective and non-conscious particles and fields of force. To be sure, we do not know exactly all the neurophysiological details of how systems of physical particles give rise to consciousness and subjectivity. Nevertheless, this ignorance is irrelevant, in Searle’s view, to the elementary fact that consciousness is a macro-feature of a physical micro-system in a similar way as liquidity or photosynthesis is. There is, however, a deep intuitive reason why many people do not feel satisfied with this answer: whereas it is easy to conceive how solidity or digestion is realized in and caused by non-liquid and non-digestive micro-particles, it is not easy to do so with respect to subjective consciousness and objective non-conscious particles. Searle interprets this difficulty as a mere misguided attempt of our imagination to picture what cannot be pictured. If we try to draw a picture of someone else’s consciousness, we just end up drawing the other person [i.e. his or her behavior and the physical make-up and the causal relations between the two] [...]. If we draw our own consciousness, we end up drawing whatever it is that we are conscious of. [...] There is, in short, no way for us to picture subjectivity as part of our world view because, so to speak, the subjectivity in question is the picturing. The solution is [...] to stop picturing [...] and just acknowledge the facts. [...]” (1992: 96-99) Further on, Searle explains a bit the reason why consciousness cannot be pictured as a macro-feature of a non-conscious micro-system, [W]e cannot […] form a picture of the necessity of the relation between subjectivity and neurophysiological phenomena, because we are already in the subjectivity, and the picturing relation would require that we get outside it. (If solidity were conscious, it would seem to it mysterious that it was caused by vibratory movements of molecules in lattice structures, but all the same those movements explain solidity.) [1992: 102-103, emphasis mine] I see at least two difficulties with Searle’s suggestions. First, the whole discussion as presented by Searle is unsatisfactorily metaphorical and imprecise. What does it mean to be “in the subjectivity”? What light sheds the inquiry into the thoughts of Mr. Solidity? Second, Searle interprets the problematic character of his analogy to be a difficulty with “picturing”. In my opinion, however, the difficulty lies not on the level of picturing but on the level of conceptual conceivability: Solidity, liquidity, photosynthesis, etc. are macro-features explicable by features of physical micro-elements and the structural and dynamical relations among them (to put it in a simplified way, solidity occurs when micro-particles stick to each other rigidly, liquidity when they do not, photosynthesis consists of a complicated interaction among light and various particles, etc.). In contrast, the mental with its property of subjectivity and consciousness can never be a feature explicable by features of physical particles and fields as we know them from our contemporary science. It is as if one hoped that lines, squares, and points with their properties could eventually explain the property of having weight. Maybe, in the future, physics shall acknowledge that the physical particles have some special, elementary quasi-mental properties so that consciousness would indeed be just another property of physical systems similarly as solidity or photosynthesis. As for now, however, we may conclude that conscious minds with their subjective ontology do not fit into the ontology of our contemporary physical and biological sciences - certainly not in the way that solidity and photosynthesis do5.
2.2. Irreducibility of the Mental MattersNow we come to Searle’s claim that conscious minds are ontologically (though not causally) irreducible to physical particles and fields but that this ontological irreducibility of mind is a trivial matter, perfectly compatible with the fact that all reality consists entirely of physical particles in fields of force. I argue, first, that Searle’s discussion of mind’s ontological irreducibility is at best terminologically confused. Then, I try to point out the flaws in Searle’s defense of the triviality of that irreducibility. My basic point is that Searle falsely assumes that from our scientific world view it follows that everything (minds included) is causally reducible to physical particles and fields of force.
The fact of causal reducibility of consciousness follows for Searle obviously from the “scientific” world view - there exists nothing but physical particles and fields and therefore they are the only available entities to account for the causal powers of conscious minds (I shall come back to this point later). Ontological irreducibility, however, needs argumentation and Searle offers some along the following lines: Let us suppose that John is in a conscious mental state such as, for instance, pain. There are two facts in virtue of which the statement “John is in pain” is true. First, it is the fact that John has some unpleasant sensations. This is something that only John, from his subjective first-person perspective, can experience. It is these unpleasant sensations that make the statement “John is in pain” true. Second, however, we know from science that John’s pain is caused by certain neurophysiological processes and so it is also in virtue of the fact that these processes occur that the statement “John is in pain” is true. Now for various reasons it would be tempting to say that the former fact is nothing but the latter, i.e., it would be tempting to try to carry out an ontological reduction. This, however, is impossible since the two relevant features constituting both facts are quite different: there is a patent contrast between the subjectivity and what-it-is-like character of John’s pain and the objectivity of his neurophysiological states (Nagel 1974). Another way to make the same point is to realize that even if one possessed a complete knowledge of the neurophysiology of John’s pain but did not have an actual conscious experience of it one would still not have the knowledge of what John’s pain is (Jackson 1982) . And since what has been said about one type of conscious states (pain) holds true about all types, i.e., about the consciousness as such, Searle concludes that conscious minds cannot be ontologically reduced to physical particles and fields. At first sight Searle’s claim about the ontological irreducibility of consciousness contradicts his physicalism. Trivially, if only physical particles and fields were to exist then by logical necessity conscious minds have to consist of nothing but physical particles and fields. And this state of affaires, I think, is to be appropriately called “ontological reducibility of conscious minds to physical particles and fields”. “Ontological” since it is about the way the world is, “reducibility” since objects of one type (minds) are held to be nothing over and above objects of another type (physical particles and fields). But we may notice that Searle does not say that ontological reduction is “the form [of reduction] in which objects of certain types are held to consist in nothing but objects of other types” but that it is “the form in which objects of certain types can be shown to consist in nothing but objects of other types [emphasis mine].” Maybe what Searle has in mind is the following: we know that conscious minds are nothing but physical particles and fields but we cannot show it. This interpretation is further confirmed by Searle’s suggestion that in the future, conscious minds might after all be shown to consist in nothing but physical particles and fields (We know the truth about the ultimate constituents of reality but we are not able to show it at present though perhaps in the future): When I speak of the irreducibility of consciousness, I am speaking of its irreducibility according to standard patterns of reduction. No one can rule out a priori the possibility of a major intellectual revolution that would give us a new—and at present unimaginable—conception of reduction, according to which consciousness would be reducible. (1992: 124) To me, however, the irreducibility of consciousness in this sense should clearly be called “epistemic” since it has to do not with the way the world ultimately is but with what can be shown - and even that not in principle but according to our present intellectual standards. I am puzzled, therefore, by Searle’s explicit insistence that his point is ontological and not epistemic7. I cannot help not to consider his assertions to be a terminological confusion. Non-triviality of the Irreducibility of the Mind Now, let us not quarrel over words and look instead on Searle’s arguments for the triviality of mind’s irreducibility (be it irreducibility epistemic or ontological). I begin by quoting and briefly discussing two passages characteristic for Searle’s view. Then I continue by an attempt to reconstruct the line of Searle’s argument and by pointing out some flaws in it. My main point against Searle concerns the falsity of one of his theses/assumptions, namely that it follows from the present-age scientific world view that everything is causally reducible to physical particles and fields. What counts as a success in modern science, argues Searle, is a reduction of a macro-phenomenon to its causal micro-basis. Thus, for instance, heat is discovered to be nothing but the kinetic energy of molecule movement, color nothing but electromagnetic waves of certain range of length, solidity nothing but the atomic and molecular attractions and repulsions, etc. It would seem that reductions lead to the elimination of the original, apparent phenomena (heat, colors, solidity etc.) and to the discovery of the new, real ones (molecules, waves). Searle, however, dismisses this impression: It [...] looks like a new discovery that heat is nothing but mean kinetic energy of molecule movement, and that if all subjective experiences disappeared from the world, real heat would still remain. But it is not a new discovery, it is a trivial consequence of a new definition [emphasis mine]. [1992: 121] So, what happens is not that heat is proved to consist in nothing but the mean kinetic energy or solidity in nothing but the forces among the atoms in the empty space. What happens in fact is that after the discovery of the causal basis of a given phenomenon the scientific community decides to revise the pre-theoretical terminology as to exclude from it the phenomenon’s subjective and experiential character. Searle believes that here lies the explanation of the irreducibility of consciousness in the universe of reducible phenomena: In general, the pattern of our reductions rests on rejecting the subjective epistemic basis for the presence of a property as part of the ultimate constituent of that property. We find out about heat or light by feeling and seeing, but we then define the phenomenon in a way independent of the epistemology. [...] But this shows that the irreducibility of consciousness is a trivial consequence of the pragmatics of our definitional practices. [...] Pretheoretically, consciousness, like solidity, is a surface feature of certain physical systems. But unlike solidity, consciousness cannot be redefined in terms of an underlying microstructure, and the surface features then treated as mere effects of real consciousness, without losing the point of having the concept of consciousness in the first place. (1992: 122-123) Now, Searle’s argument appears at this point to be rather tangled and so let me try to make its structure more visible: Searle’s main theses: I. (a) Conscious minds are causally, (b) though not ontologically reducible. II. Ontological irreducibility of consciousness is a trivial consequence of our "definitory pragmatics" (the way we make definitions). Justification of I: causal reducibility follows from our “scientific” world-view, ontological irreducibility from Nagel-Jackson-Kripke argument. Justification of II: 1. With respect to non-conscious phenomena reduction works as follows: 1.1 Causal reduction: Some micro-phenomena (physical particles and fields, henceforth PPF) are found to be the cause of a macrophenomenon other than consciousness, e.g. solidity, heat, photosynthesis etc. (henceforth M-x) 1.2 Ontological reduction: M-x is said to be nothing but PPF 2. With respect to consciousness reduction would work as follows: 2.1 Causal reduction: one day (hopefully) there will be found microphenomena (PPF) which cause the macrophenomenon of consciousness (henceforth M-consciousness) 2.2 Ontological reduction: Trivially, M-consciousness cannot be said to be nothing but PPF
3. M is in fact ambiguous, since it is to be distinguished between a) macrophenomenon as it is in itself, apart from any form of conscious experience (henceforth M1), b) conscious experience of a macrophenomenon (henceforth M2) . 4. Given the new distinction it may be specified that the sentence 1.2 is to be interpreted “M1-x is nothing but PPF” and not “M2-x is nothing but PPF” 5. “M1-x is nothing but PPF” is a definition of M1-x by means of PPF, not a new discovery – the discovery is 1.1 6. M-consciousness cannot be defined as M1-consciousness by means of PPF from trivial reasons: M1-consciousness is an oxymoron (macrophenomenon of consciousness as it is, apart from any conscious experience). 7. M-consciousness must be defined as M2-consciousness and since ontological reduction applies only to M1-x, from trivial reasons of our definitory pragmatics (cf. 6) consciousness is ontologically irreducible. Quod erat demonstrandum. I am not sure whether Searle would endorse my reconstruction of the line of his argument but this is the best I can make out of it. Now, needless to say, one can question virtually any step in it. For instance, Ad 1.1: The general validity of causal reducibility is uncertain not only with respect to consciousness but also with respect to other phenomena. (Is chemistry reducible to physics and biology to chemistry?). Also, the realism in physics is not unchallenged (there are philosophers which consider the picture suggested by physics as instrumental but not representative of the reality – they believe that in fact there are no protons or electrons). Ad 1.1, 2.1, etc.: The talk of micro- and macro- phenomena may be misleading. The assumption is that micro- always explains the macro- but it is not generally so, not even in physics (radio waves cannot be said to be micro, they are huge, but they consist of elementary particle/waves photons). What is relevant is not the size (micro, macro) but ontological priority or dependency. Ad 1.2: As I have already pointed out, ontological reduction should be rather appropriately characterized as “M-x is nothing but PPF” and not “M-x is said to be nothing but PPF”. Ad 4: From which reasons the sentence 1.2 is to be interpreted “M1-x is nothing but PPF” and not “M2-x is nothing but PPF”? (In other words, why is ontological reduction applied only to macrophenomena as they are in themselves, apart from any form of conscious experience?) Ad 7: Similarly as in 4 – Why is ontological reduction applicable only to M1-x and not to M2-x? One could expand and work out the list but in my opinion, within Searle’s framework none of these questions and difficulties is insurmountable. The deeper reason why I consider Searle’s argument unsuccessful lies in the first part of his thesis/premise: from the scientific world view it follows that everything is causally reducible to PPF. Now what is the status of the sentence “everything is causally reducible to PPF” – is it a contingent or necessary truth? Let us suppose that it is a contingent claim and that it is a discovery about the world. Then, however, it seems to be false or at best ungrounded: Similarly as the sentence 1.2 construes “M1-x is nothing but PPF” sentence 1.1 construes “PPF is the cause of M1-x”. Consequently, M2-x remains causally unexplained and no pre-theoretical notion such as color, solidity, heat etc. has so far ever been causally explained. If that is the case then how can one claim that from the scientific world-view it follows that everything is causally reducible to PPR? But let us suppose that the sentence “everything is causally reducible to PPF” is a necessary claim. Then, however, “everything” ranges over M1-x but not over M2-x (and M-consciousness) since “M1-x is nothing but PPF” defines M1-x (cf. 5) but does not define M2-x (and M-consciousness)8. That is, if the sentence “everything is causally reducible to PPF” is understood as a necessary claim then it does not apply to conscious experiences and consciousness. So, either way we interpret the sentence “everything is causally reducible to PPF” it cannot be true (even within Searle’s framework) that science teaches us that M-consciousness is causally reducible to PPF. If my previous considerations are sound then Searle’s whole argument for the triviality of mind’s ontological irreducibility does not stand well. Furthermore, as we shall see in the next section, there is also another argument against the causal reducibility of conscious minds, proposed by Nagel. Needless to stress, causal irreducibility of minds presents a serious obstacle to Searle’s thoroughgoing physicalism, one of the fundamental pillars of his ontology. 2.3. Nagel’s Argument for Causal IrreducibilitySearle himself acknowledges that there is a powerful argument against the causal reducibility of minds. It has been proposed by Thomas Nagel (1974) and in my modification it goes as follows9: Premise 1: Causal explanations in science involve a kind of necessity10 (e.g. the molecular theory does not only show that such and such systems will be under such and such circumstances in such and such form - it shows why they have to be.) Premise 2: No account could (conceivably) explain why, given such and such neural state, e.g. C-firing, we have to be in such and such conscious state, i.e. pain. (The correlation between the two types of states is determined by observation and we can always conceive of a quite different result). Conclusion: It is inconceivable that in science we could have a causal explanation of consciousness (i.e. that we could carry out a causal reduction of consciousness).
(1) Not all explanations in science involve necessity – for instance, the inverse square law is a scientific account of gravity, but it does not show why physical bodies have to have gravitational attraction. Consequently, a possible future scientific account of consciousness does not have to involve some kind of necessity. (2) At present we don’t know but a future scientific account of consciousness could possibly make us see that given such and such neural state, e.g. C-firing, we have to be in such and such conscious state, i.e. pain. In Searle’s words:
In my opinion, there are difficulties with each of Searle’s strategies. (1) It is true that the inverse square law of gravity, similarly as many other scientific laws, does not involve a kind of necessity. From this fact, however, it does not follow that the inverse square law of gravity is an instance of a causal explanation lacking a kind of necessity. On the contrary, this means that the inverse square law of gravity is not a causal explanation. The inverse square law of gravity is a mathematical way of expressing an observable regularity and its function is merely descriptive, not explanatory. In fact, we still do not have a causal explanation of gravity, we still do not understand this phenomenon well enough, though we have some sort of rough idea how the causal explanation of it will probably look11. If we had one we would know why physical bodies have to have gravitational attraction and not only that they have it. Nagel’s point was precisely to show that whereas in science we have, either actually or conceivably, explanations involving necessity, we cannot have such explanation with respect to consciousness. When it comes to consciousness we must be satisfied with the observation and exploration of regularities such as, “whenever patient reports such and such conscious state (pain), his or her neural state is such and such (C-firing)”. In other words, since no scientific account of consciousness (existing or conceivable) involves necessity, no scientific account of consciousness (existing or conceivable) can make consciousness causally reducible. (2) Searle speculates that maybe we could after all find an account of consciousness that is so convincing that we see a necessary connection between a neural state, e.g. C-firing and the appropriate conscious state, i.e. pain. This, however, is a mere speculation and no good reason has been given in favor of it. As far as our present science and present knowledge is concerned, consciousness appears to be causally irreducible, since we cannot even conceive of such an account of consciousness which would establish some kind of a necessary correlation between conscious and neurophysiological states. (3) The structure of the discussion goes as follows: Searle holds that R (the “scientific” worldview) justifies the belief B (the mind is causally reducible). Nagel argues that it is inconceivable how R and B could both be true. This indicates that R and B might be inconsistent since if something is inconceivable there is a good reason to believe that it is inconsistent. The inconceivability of the causal reducibility of consciousness sufficiently justifies the thesis that consciousness is irreducible – Searle is wrong in taking inconceivability as irrelevant to our knowledge of how the world in fact is12. All in all, Searle does not appear to deal successfully with Nagel’s argument, which presents a serious difficulty for the consistency for his ontology. Appendix: Is Searle a Property Dualist? In Searle’s view the “traditional” ontology (which for him amounts to the ontology of Descartes and his heirs) is deeply mistaken when it introduces two radically different types of things – minds and material bodies. We live in the one and only world and this world has both what we think of as mental and what we think of as physical features. Still, it would seem undeniable that though perhaps there does not exist two types of things such as res cogitans and res extensa one must acknowledge at least two types of properties – the mental and the physical. But Searle vigorously denies even such a weaker view (e.g. 1992: 13). “Mental,” does not imply for him “non-physical” and “physical” “non-mental”. In fact, Searle insists that whatever is mental is at the same time physical: “consciousness qua consciousness, qua mental, qua subjective, qua qualitative is physical, and physical because mental.” (1992: 15) But one must ask further „Is it also the case that whatever is physical is at the same time mental?“ And unless one is panpsychist or neutral monist the answer is “no”. So, trivially, since Searle is neither panpsychist nor neutral monist, he has to acknowledge two types of properties in some sense: non-mental physical (objective) and mental physical (subjective)13. Given that how shall one understand Searle’s strong verbal protests against his ontology being denoted “property dualism”? There are at least two explanation, I think. The first I see in a connotation that the expression ‘property dualism’ carries – an equality in the ontological status of the two properties (both are ontologically fundamental). Needless to say, this connotation is for Searle unacceptable since in his view there exist individuals which are objective (non-mental physical) without being subjective (mental physical) but not individuals which are subjective without being objective, i.e. the objective properties are ontologically prior to and more fundamental than the subjective ones. Another reason can be found, I think, in the following observation:
Now, it is fair to say, that in a sense Searle is not a property dualist but a property pluralist – his ontology acknowledges an immense variety of kinds of properties. In another sense, however, he is a monist since the ultimate building blocks are physical elements and fields of force and all the immense variety of macro-properties is (at least causally) reducible to them. But is it not the case that the distinction between the non-mental and the mental (which, as we have seen, Searle must within his ontology acknowledge) is of such an importance as to make the denomination ‘property-dualism’ for Searle’s ontology appropriate? 3. ConclusionIn my paper I have tried to evaluate Searle’s ontology of mind in the universe – a position in philosophy which Searle himself calls ‘biological naturalism’. In the first section of my paper I have discussed Searle’s arguments for the reality of mind. I agreed with Searle that the mental has to be accounted for in any adequate and complete ontological theory. In the second section of my paper I criticized Searle’s arguments that conscious and irreducible minds fit perfectly into the physicalist world view, according to which everything consists entirely from physical particles and fields of force. Since Searle’s defense of his views is complex I have focused on three elements which I consider to be the weakest. First, I argued that Searle’s analogy between solidity and consciousness as a macro-feature of a micro-system fails to illuminate the unproblematic character of the mental in the physical world. Second, I criticized Searle’s defense of the ontological irreducibility of consciousness as, given Searle’s physicalism, terminologically confused and non-trivial. Third, I defended Nagel’s anti-physicalist argument (showing the causal irreducibility of conscious minds to the ontology of contemporary physics). Searle’s attempt to reconcile physicalism and mentalism is interesting and stimulating. Nevertheless, as I have attempted to show, it is unsuccessful14. Historically, Searle is not the first to hold that mind is physical – before him it was Aristotle who argued for such view. But Aristotle’s concept of physics and even his concept of mind differs radically from today’s understanding (Code 1991 for physics, Kenny 1989 for mind). It would be not therefore a straitforward task to cast Aristotelian solutions into the contemporary context. Still, given the impass which Searle’s approach has reached, re-considering Aristotle’s alternative views would seem to me a worthy attempt.
Chalmers, David J. (1996). The Conscious Mind: In Search of a Fundamental Theory. New York, Oxford: Oxford University Press. Code, Alan (1991) “Aristotle, Searle, and the Mind-Body Problem,” in Lepore and Van Gulick (1991), pp. 105-113. Descartes, Rene. (1983) Principles of Philosophy. Translated, with explanatory notes, by Valentine Roger Miller and Reese P. Miller. D. Reidel Publishing Company: Dordrecht, Holland; Boston, MA; London, England. Gracia, Jorge J. E. (1999) Metaphysics and Its Task. Albany, NY: SUNY Press. Hawking, Stephen (1988) A Brief History of Time: from the big bang to black holes, introduction by Carl Sagan, illustrations by Ron Miller. Toronto, New York: Bantam Books. Jackson, Frank (1982) “Epiphenomenal Qualia,” Philosophical Quarterly 32: 127-136. [Reference taken from Searle 1992] Kenny, Anthony (1989) The Metaphysics of Mind. Oxford: Clarendon Press. Kripke, Saul (1971) “Naming and Necessity,” in D. Davidson and G. Harman (eds.), Semantics of Natural Language. Dordrecht: Reidel, pp. 253-355 and 763-769. Lepore, E. and R. Van Gulick, eds. (1991) John Searle and His Critics. Cambridge, MA and Oxford: Basil Blackwell. Nagel, Thomas (1974). “What Is It Like to Be a Bat?” Philosophical Review 4 LXXXIII: 435-450. [Reference taken from Searle 1992] Fotion, Nick (2000) John Searle. Princeton, NJ: Princeton University Press. Searle, John R. (1983) Intentionality: An Essay in the Philosophy of Mind. Cambridge (UK): Cambridge University Press. ______. (1992) The Rediscovery of the Mind. Cambridge, MA: The MIT Press. ______. (1969) Speech Acts: An Essay in the Philosophy of Language. Cambridge (UK): Cambridge University Press. 1 The reason why dualists and materialists agree on this point lies in their acceptance of what Searle calls “the exclusion principle”: nothing can be both mental and physical at the same time. Obviously, (a) and (b) are compatible if and only if the exclusion principle is false, i.e. something can be (or even is) both mental and physical. The exclusion principle involves modality which might be understood in different ways. Typically, it seems to me, it is understood in a broadly speaking logical sense - nothing can be both mental and physical as it cannot be both colored and non-extended. 2 See, for instance, Searle’s discussion of the “scientific” world view (1992:83-93). “It goes without saying that our “scientific” world view is extremely complex and includes all of our generally accepted theories about what sort of place the universe is and how it works. […] Some features of this world view are very tentative, others well established. At least two features of it are so fundamental and so well established as to be no longer optional for reasonably well-educated citizens of the present era; indeed they are in large part constitutive of the modern world view. These are the atomic theory of matter and the evolutionary theory of biology. […] According to the atomic theory of matter, the universe consists entirely of extremely small physical phenomena that we find it convenient, though not entirely accurate, to call “particles.”[Emphasis mine]” (1992: 85-86). 3 “Cogitationis nomine, intelligo illa omnia, que nobis consciis in nobis fiunt, quatenus eorum in nobis conscientia est. Atque ita non modo intelligere, velle, imaginari, sed etiam sentire, idem est hic quod cogitare.” (AT VIII, 7) 4 “I was appalled to discover that with few exceptions [… the standard] authors routinely denied what I though were simple and obvious truths about the mind. It was then, and still is, quite common to deny, implicitly or explicitly, such claims as the following: We all have inner subjective qualitative states of consciousness, and we have intrinsically intentional mental states such as beliefs and desires, intentions and perceptions.” (Searle 1992: xii) 5 Another way to put it: Physics teaches us that particles and fields have certain properties (whatever they are – mass, energy, spin etc.). Now macro-objects consisting from these particles and fields have the same type of properties, i.e. mass, energy, etc., as the elements from which they consist plus properties given by spacial and temporal formation of the elements (solidity is a macro-property of micro-elements held by mutual forces in lattice structures, photosynthesis is a macro-property of micro-elements undergoing various transformations in space and time, etc.). The property of being conscious, however, obviously can be neither property of micro-elements nor a property given by the spacial and temporal formation of the micro-elements. To claim otherwise is to endorse futile hopes similar to those of Descartes (from the elements having only extensionality there were to be „deduced“ objects having color, weight and all other types of properties). 6 Searle also mentions other forms of reduction (property ontological, theoretical and logical) but in our context he does not consider them relevant and so we can leave them aside (1992: 113-4). Searle mentions also Kripke’s variety of the argument (1974). I omit it since it is more technical, formulated in terms of rigid designators and possible worlds semantics. 7 “I think the argument [for ontological irreducibility] is decisive, though it is frequently misunderstood in ways that treat it as merely epistemic and not ontological. It is sometimes treated as an epistemic argument to the effect that, for example, the sort of third-person, objective knowledge we might possibly have of a bat’s neurophysiology would still not include the first-person, subjective expereince of what it feels like to be a bat. But for our present puposes [???], the point of the argument is ontological and not epistemic. It is a point about what real features exist in the world and not, except derivatively, about how we know about those features.” (1992: 117) Especially the last sentence appears as if Searle wanted to suggest that the point of the argument is to convince the skeptics of the existence of conscious minds. But it would be a mistake - what is at stake is not the existence of conscious minds but their reducibility to physical particles and fields. These two problems are clearly distinct (similarly, the question of the existence of solidity is not the question of its reducibility). This distinction seems to me to be a necessary condition of the inteligibility of Searle’s discussion though I do not know what Searle would say about it explicitly. See, for instance, „[w]e can summarize [...] from the point of view of the property dualist as follows: The apparent contrast between the irreducibility of consciousness and the reducibility of color, heat, solidity, etc., really was only apparent. We did not really eliminate the subjectivity of red, for example, when we reduced red to light reflectances; we simply stopped calling the subjective part “red.” We did not eliminate any subjective phenomena whatever with these “reductions”; we simply stopped calling them by their old names.“ (Searle 1992: 123) Searle clearly distinguishes here between red-as-consciously-experienced (my M1) and red-as-electromagnetic-reflectances (my M2). 8 In fact, the notion of cause in contemporary science appears to be applicable only in the realm of PPF and M1. 9 The original context of the argument is the discussion of the body-mind problem (1992: 100-105). Nagel’s argument was to show that we lack conceptual apparatus even to conceive of a solution, whereas in Searle’s opinion the problem is not that difficult. Searle sees only two obstacles to solving it: first, the false assumption that the mental and the physical are two distinct realms; second, our ignorance of the exact workings of the brain. 10 Throughout the discussion of Nagel’s argument I operate with the notion of necessity. Now, notoriously, this notion (or rather cluster of notions) has been highly difficult and controversial. For my purposes, however, it is sufficient to say that what I have in mind is not logical but something like natural or causal necessity. Intuitively, when one billiard ball hits another, it is causally necessary that the other sets into motion. 11 The search for the ultimate understanding of gravity motivates much of the work in contemporary theoretical physics. Cf. Stephen Hawking’s speculations about the unified quantum gravity theory (1988). 12 It maybe that Searle refers here to picturability (concerned with the powers of imagination) and not to conceivability (powers of conception). Nagel’s argument, however, concerns conceivability and so Searle would avoid the discussion. Cf. also 2.1 of my paper. 13 Moreover, Searle explicitely writes that the distinction between mental (subjective) and non-mental (objective) is an ontological one: “[I]n the sense in which I am here using the term, “subjective” refers to an ontological category, not to an epistemic mode.” (Searle 1992: 94) 14For a similar claim, namely that Searle’s position is not quite coherent, see e.g. Chalmers (1996: 375-6, n. 34). Download 109.17 Kb. Share with your friends:
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