Mental Representation and the Subjectivity of Consciousness
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PHILOSOPHICALPSYCHOLOGY , VOL. 14, NO. 2, 2001 Mental representation and the subjectivity ofconsciousness * PETE MANDIK ABSTRACT Many haveurged that the biggest obstacles to a physicalistic understanding of consciousness arethe problems raised in connection withthe subjectivity ofconsciousness. These problemsare most acutely expressed in considerationof theknowledge argument against physicalism. Idevelopa novelaccount of the subjectivity of consciousness byexplicatingthe ways in whichmental representationsmay be perspectival. Crucial featuresof my accountinvolve analogies between the representationsinvolved in sensoryexperience and theways in which pictorialrepresentations exhibit perspectivesor points of view. Iarguethat the resultant account of subjectivity provides a basisfor thestrongest response physicalists can giveto the knowledge argument. Introduction Consciousness has beena real pain forphilosophers and cognitive scientists inter- estedin developing materialist theoriesof the mind. Particularly vexing is the subjectivity ofconsciousness: thesubjective characterof conscious experience. What subjectivity is and whyit posesproblems for physicalists emergesmost vividly in discussions focusing onthework of philosophers Thomas Nagel and Frank Jackson. Nagel (1974) famously asked “whatis it like tobe a bat?”and urged thathumans, notbeing bats, could never know. Mostimportantly in his criticism ofthe limits of physicalism, Nagel argued thatno amount ofknowledge ofthe objective physical factsabout bat brains could yield knowledge ofthe subjective characterof bat experience. Whatis known fromthe objective point of view cannot bridge thegulf toyield whatis known fromthe subjective pointof view: knowledge of what it is like . Drawing on similar intuitions, Jackson marshaled thesethemes in an attemptto falsify physicalism by way ofhis nowfamous knowledge argument .The gist ofthe knowledge argument is as follows.Mary has never seen red. She nonethelessknows all thephysical facts. Upon seeing red forthe rsttime, Mary learns something new: what it is like tosee red. Priorto seeing red, Mary knewall thephysical facts; thus *This paper was the winnerof the 2000William James Prize of the Societyfor Philosophy and Psychology, awarded for the best paper by agraduate student presentedat the Society’s annualmeeting. PeteMandik, Departmentof Philosophy, William Paterson University ofNew Jersey, 265Atrium Building, 300Pompton Road, Wayne, NJ07470,USA, email: [email protected] ISSN 0951-5089/print/ISSN 1465-394X/online/01/020179–24 Ó 2001Taylor &FrancisLtd DOI:10.1080/ 09515080120051553 180 P. MANDIK in learning anewfact upon having ared experience, Mary learns anon-physical fact. Thus thesubjective characterof experience is non-physical (Jackson, 1982). Therehave beenmany physicalist responsesto Nagel and Jackson overthe years. Mostare awed and only afewexplicitly address thetopic of subjectivity. In thispaper I develop atheoryof subjectivity and use it in adefenseof physicalism against theknowledge argument. Crucial aspectsof myaccount involve explications ofthe notions of perspective and point ofview .Icultivate an account ofperspective as it arises in pictorial representationsand apply theresultant account ofpictorial perspectiveto mental representations. Icontrastmy account against accounts that analyze perspectivesand pointsof view in termsof indexicals. Keyaspects in my arguments forthe superiority ofthe pictorial theoryof subjectivity overindexical theorieshinge on howthe respective theories are able todeal withthe issues raised in connection withthe knowledge argument. This paperis organized as follows.I begin withfurther discussion ofNagel and Jackson’s original arguments withspecial attention paid tothe role played by the notion ofsubjectivity. Ithenbrie y discuss themain kinds ofphysicalist responses toJackson’ s knowledge argument. Aftercanvassing themain kinds ofphysicalist responsesand their aws, Ilaunch into thearticulation ofmy pictorial theoryof subjectivity. Idiscuss crucial similarities and differencesbetween my pictorial theory and indexical theories,and address several possibleobjections to thepictorial theory. 1.The subjectivity of consciousness andthe knowledge argument against physicalism Nagel’s reections on objectivity and subjectivity have beendeveloped in several places, buthere I focuson his 1974 article “Whatis it like tobe a bat?”Nagel presumesthat bats are conscious, thatthere is something it is like tobe abat. Things thatlack conscious, like rocks,are things forwhich there is nothing it is like tobe. Notonly is Nagel condent thatthere is something it is like tobe a bat, heis condent thatit is radically unlike whatit is like tobe a human. This is plausible. Bats have sensory systemsquite unlike ours; mostnotably theyemploy sonar in their perceptual interaction withtheir environment. Given thedivergence betweenhu- mans and bats, humans are incapable ofknowing whatit is like tobe a bat. Imagination and extrapolation are oflittle help. Even imagining apping around and hearing ourown voices reected off of the surfaces of objects serves only totell us whatit would belike tobe us under altered circumstances—such imaginings bring us no closerto knowing whatit would belike for bats.Whatwe can knowabout bats are thedeliverances ofobjective physical sciences: factsand propertiesknowable frommultiple pointsof view— objective facts. The factsabout batsbeyond our purview are thesubjective facts:facts known, if at all, only fromthe point ofview of bats. Acrucial point tonote, and onethat I will return toseveral timesin thispaper, is thatNagel intends theseremarks about perspectivesand pointsof view tobe about types and not tokens.Nagel writes: Iam notadverting hereto thealleged privacy ofexperience toits possessor. The point ofview in question is notone accessible only toa single MENTAL REPRESENTATION 181 individual. Ratherit is a type. Itis oftenpossible to take up apoint ofview otherthan one’s own, sothe comprehension of such factsis notlimited to one’s owncase. Thereis asense in whichphenomenological factsare perfectlyobjective: one person can knowor say ofanotherwhat the quality ofthe other’ s experience is. They are subjective, however,in thesense that even thisobjective ascription ofexperience is possibleonly forsomeone sufciently similar tothe object of ascription tobe able toadopt his point ofview— to understand theascription in the rstperson as well as in the third, soto speak. The moredifferent from oneself the other experiencer is, theless successone can expectwith this enterprise. (1974, pp. 441–442) Nagel thusurges thatwhat we are cutoff from are factsabout certain properties— universals orrepeatables thatare instantiable by multiple individuals. Nagel’s arguments are nottargeting theepistemic problem of knowing theminds ofthose thatare merely numerically distinct fromyou, aproblemthat could arise between you and an otherwiseidentical twin. Nagel is instead concerned topoint outa problemthat arises in trying tocomprehend a quite qualitatively distinct kind of mind. Nagel castshis criticism as pointing outthe limits ofcurrent physicalistic understanding, buthe does not see it as falsifying physicalism. While hehas no doubt that physicalism about subjectivity is true, Nagel says thatwe cannot currently understand how it is true. Jackson, in contrast, cultivates Nagelian themesinto an argument against physicalism: theknowledge argument. Jackson’s knowledge argu- mentinvolves twothought experiments, onemore famous than theother. The famousthought experiment featuresMary, thephysically omniscient scientist who only comesto learn whatit is like tosee red late in life. Lessfamous is thethought experiment thatfeatures Fred. WhereMary spends mostof herlife restrictedto the black and whiteroom and thusseeing farfewer colors than theaverage human, Fred is gifted withan unusually sensitive visual systemand thussees more colors than the average human. Whereaverage humans might group asetof ripetomatoes together as all being thesame shade ofred, Fredsorts the tomatoes into twogroups thathe calls red1 and red2. Fredassures us thatred1 and red2 are as differentfrom each otheras yellow and blue. He sortsthe same objectsinto thesame groups trial after trial, giving evidence thatthe perceptual categories thathe is tapping into are quite salient and robust.Fred’ s reportsand behavior make us condent thatwhat it is like tobe Fred is differentfrom what it is like tobe a normal human. However, wedo notknow what it is like tobe Fred. Wemay acquire all ofthe physical information about howFred’ s nervous systemworks and whatphysical featuresof objects he is sensitive to,but this is insufcient togive us knowledge ofwhat it is like. According toJackson, however,there are otherconditions thatwill sufce to give us knowledge ofwhat it is like tobe Fred. Jackson invites us toimagine thathumans have their visual systemssurgically altered toresemble Fred’ s, orupon Fred’s death someone else receivesa transplant ofFred’ s visual system. Afterthese surgeries, peoplewould cometo learn something new—what it is like tobe Fred. Priorto the surgery, however,the regular humans knewall ofthephysical factsabout Fred. So in coming 182 P. MANDIK tolearn something new, theycome to learn something non-physical. Thus physical- ism is false since notall ofthe facts are physical facts. Like Nagel, Jackson urges thatthese remarks about thesubjective characterof experience target apointabout typesof minds, nottokens. Jackson writes: When Icomplained thatall