Varieties of Phenomenal Externalism

teorema Vol. XXVIII/1, 2009, pp. 21-31 [BIBLID 0210-1602 (2009) 28:1; pp. 21-31]

Varieties Of Phenomenal Externalism

Johan Veldeman

RESUMEN El externismo fenoménico es la tesis según la cual las experiencias no son estados internos que están en la cabeza, sino relaciones entre perceptores y su entorno. Se presta atención a tres tipos de externismo fenoménico: a saber, el externismo en cuanto al contenido, el externismo en cuanto a los vehículos del contenido, y el realismo directo. Se argumenta que los dos primeros tipos no dan cuenta de la conciencia, y que sólo el realismo directo sustenta una forma robusta de externismo.

PALABRAS CLAVE: conciencia fenoménica, externismo, percepción.

ABSTRACT Phenomenal externalism is the view that experiences are not inner states in the head but relations between perceivers and the environment. Three different types of phenomenal externalism will be considered, that is, content externalism, vehicle externalism, and direct realism. It will be argued that the first two types fail to accommodate consciousness, and that only direct realism supports a robust kind of externalism.

KEYWORDS: phenomenal consciousness, externalism, perception.

I. THREE ROUTES TO PHENOMENAL EXTERNALISM

Phenomenal externalism is the view that the phenomenal properties of perceptual experiences, that is, the subjective ways things appear to us as conscious agents, are ‘not in the head’. This should not be misunderstood as the absurd view that experiences are ‘out there’ in the world, having their own existence independently of the subjects who entertain these experiences. Phe- nomenal externalism says that perceptual experiences, their content and phenomenology, should not be understood in terms of inner states in the subject’s brain or mind but, rather, in terms of some relation between minded creatures and external objects and properties. Thus externalist views on phenomenal consciousness may be more accurately termed ‘relational’ views. If phenomenal externalism is true, then this has important consequences for the ongoing discussions about whether a physicalist, reductionist account of consciousness is possible. These discussions proceed on the basis of the

21 22 Johan Veldeman presupposition that phenomenal character is an intrinsic feature of a perceptual state, directly accessible to introspection, and separable from its representational content in virtue of which it is related to the world. If phenomenal experiences are relations between subjects and external objects and properties, then some central questions about the nature of phenomenal consciousness will turn out to be seriously misconceived. Phenomenal states may not be reducible in physical terms, not because naturalism is false, but because they are not inner qualities in the head. My aim in this paper is not to defend phenomenal externalism against persistent internalist intuitions. Rather, it is to elucidate the concept of phenomenal externalism and to consider what a plausible version of it may look like. I shall consider three independent routes that may be taken to lead to phenomenal externalism. The first is the route from ‘reference’ or ‘meaning’ to the phenomenal mind, which I shall call ‘content externalism’. The second route, which I shall call ‘vehicle externalism’, infers phenomenal externalism based on considerations about the active and extended nature of cognition. The third route, ‘direct realism’, takes the relation between the subject, rather than some of her mental states, and worldly items to be fundamental. I shall defend this third route as supplying the most robust type of externalism. I shall argue that the first two forms of externalism fail to properly accommodate consciousness and therefore fail to support phenomenal externalism. As a consequence, they need independent support from direct realism.

II. FROM ‘MEANING’ TO MIND:CONTENT EXTERNALISM

Content externalism is the most popular form of externalism. It derives from Hilary Putnam’s (1975) Twin-Earth intuitions that show that the reference and truth conditions of mental-state ascriptions are externally determined. Hilary Putnam’s so-called ‘Twin-Earth’ thought experiment is familiar: We are asked to imagine a planet that is just like earth except in one respect: H2O is replaced by a chemical substance with the molecular structure XYZ, which has all the observable characteristics of water. So whereas on earth lakes and rivers are filled with H2O, on Twin Earth they are filled with XYZ. English-speaking Twin-Earthians use their expression ‘water’ in exactly the way we use ‘water’. But our ‘water’ and Twin-Earthian ‘water’ have different extensions: the first refers to H2O, whereas the second refers to XYZ. So, when both my Twin-Earth counterpart and I use the expression ‘water’, our expressions differ in meaning, even if we might be in exactly the same brain state and if our speech behaviour might be undistinguishable. Putnam’s Twin-Earth has inspired many philosophers to explore the consequences of externalism about reference and meaning for the philosophy of mind. Philosophers like Tyler Burge (1979, 1986) and Colin McGinn (1982) Varieties Of Phenomenal Externalism 23 have proposed an extension of Putnam’s semantic externalism to the contents of propositional attitudes as well. The basic idea is that propositional attitudes are identified by way of their contents, that is, by their semantic properties. For instance, what makes a belief into the belief that water is wet is its relation to its content, which is simply the proposition ‘water is wet’. And so, if linguistic meaning is necessarily bound up with one’s causal relations to certain natural substances, then the same holds for mental content. Today, content externalism is widely assumed to be applicable to mental representations generally. Representationalists about phenomenal consciousness, such as Fred Dretske (1995a, 1995b) and Michael Tye (1995), argue that the scope of Put- namian externalism may be broadened to be applicable to the phenomenal character of perceptual experience. Representationalists identify the phenomenal character of a perceptual state with a particular content of a sensory representation. If phenomenal character can be reduced to a certain type of representational content, then the scope of externalism may extend to phenomenal character as well. Microphysically identical twins might differ not only psychologically but also phenomenologically. Thus, thinking about water is externally determined for it requires the existence of water in the environment of the thinker. Similarly, and by extension, a red experience is externally determined for it requires the existence of redness in the environment of the perceiver. What makes a state of the brain into an experience of a certain type is some causal relation with an external phenomenon. A sensory representation represents red, for instance, if redness is its ‘normal cause’, which is determined by the evolutionary history of colour vision. Has representationalism successfully extended the scope of externalism to experience? In my view it has not. Representationalism attempts to explain perceptual content exclusively in terms of sensory information. As such, sense experience is taken to manifest a kind of intentionality that is distinct and more basic than that involved in propositional thought and conceptual understanding. Dretske and Tye defend broadly similar views that depend heavily on the idea that the content of perceptual experience is essentially nonconceptual, that is, independent of belief. Moreover, perceptual content is not taken to be object-involving: experiences represent basic visual properties such as size, shape, colour and motion, but they do not represent individuals. Phenomenally conscious states are distinguished partly by their possession of that special type of content. Thus when I look at an apple, for instance, my visual system represents some of the surface properties of its facing side, independently of my belief that there is an apple in front of me. Whether or not a particular apple is present, or whether there is no apple at all, as in cases of hallucination, is not a part of the content of experience. The aspects of context which fix the reference of a perceptual experience are not themselves assumed to be available to the subject. Thus an experience represents things as 24 Johan Veldeman having properties but it does not by itself represent the object that has the properties. What makes a visual experience a representation of a particular thing is simply a contextual relation that is not represented in experience. This yields a context-free type of content shared by visual perceptions and hallucinations.1 A veridical visual experience and an undistinguishable hallucination share the representation of common properties. Thus understood, experience is essentially non-relational; it does not bring the subject into direct contact with external things. This view is problematic, for the reason that a type of content that can be common to veridical and hallucinatory cases fails to play its explanatory role: it makes it unintelligible how our experience puts us into a position to think about an objective, mind-independent world in the first place.2 Despite their radical externalist view on what determines the contents of experiences, representationalists turn out to provide a ‘non- relational’ account of content after all. Moreover, it is fairly uncontroversial that nonconceptual states are im- plicated in plenty of nonconscious processes. In order to distinguish between those informational states which are conscious and those which are not, representationalists draw on further functionalist considerations. The common view is that the sensory representations must supply inputs to the cognitive system, and that ‘full-blown’, object-involving consciousness requires higher-order awareness of lower-level sensory states. Thus Tye writes: “Without the application of concepts, our sensations are concealed from us. We are like the distracted driver who sees the road ahead, and thereby manages to avoid crashing, but who is oblivious to his visual perceptions” [Tye (1995), p. 190]. Full-blown consciousness of the kind that the distracted driver lacks is higher-order consciousness, that is, consciousness of one’s own mental states. As such consciousness is conceived as an entirely internal affair.

III. FROM ‘COGNITION’ TO MIND:VEHICLE EXTERNALISM

Vehicle externalism is significantly different. It is a type of active externalism which asserts that the environment can play an active role in constituting and driving cognitive processes. It applies to the vehicles of mental representation, that is, the carriers of content, rather than the contents themselves. Thus vehicle externalism is a claim not merely about the determination of mental content but also about the location of mental processes. Cognitive processes such as perceiving, remembering, thinking and reason- ing, involve some sort of information processing, that is, the transformation of information-bearing structures. And according to the vehicle externalist, these extend beyond the skin of the individual. In ‘The Extended Mind’ (1998), Andy Clark and David Chalmers argue that some of the external representations we employ to solve our cognitive Varieties Of Phenomenal Externalism 25 tasks deserve to be characterized as genuinely mental representations, despite their external location. Take for instance the use of pen and paper to perform a long multiplication. Active externalism suggests that the pen and paper should be viewed as part of the substrate of the calculating activity. Clark & Chalmers also mention games like Scrabble and Tetris, and, more generally, the use of language and culture, as cases in which some cognitive operations are not restricted to processes in the brain, but are in a sense delegated to ma- nipulations of external media. In these cases the human organism and the external entity create a coupled system that can be seen as a cognitive system in its own right. Clark & Chalmers go on to argue that not just some processes, but also mental states, and, in particular, beliefs, can be constituted partly by features of the environment. They consider a patient who suffers from Alzheimer’s disease, and who always carries a notebook with him and writes down all the new information he learns. The patient has to rely on his notebook to retain information and find his way about. For the patient, consulting his notebook plays the same role that memory plays for persons with a normal functioning memory. Clark & Chalmers argue that, because the notebook plays an active role in the cognitive life of the patient, the contents of the notebook actually constitute some of that person’s non-occurrent beliefs. If the notebook is part of the belief system, this shows that mental contents can extend beyond the skin. As such Clark & Chalmers reach a conclusion that is similar to the tra- ditional Putnamian externalism, namely, externalism about belief, with the important difference that the external features constituting difference in belief are not distal or historical but “also involve differences in the dynamics of cognition” [Clark & Chalmers (1998), p. 14]. Recently, philosophers like Susan Hurley (1998), Mark Rowlands (2001, 2003) and Alva Noë (2004) have taken vehicle externalism to apply to perceptual consciousness. Vehicle externalism about perceptual consciousness is basically motivated by acknowledging the active nature of perception and is in many respects reminiscent of James Gibson’s (1979) ecological approach to perception. Gibson’s ecological approach can plausibly be seen as a vehicle-externalist approach. Central to this approach is the idea of ‘the ambient optic array’, which is the structure of light in the environment. Gibson held that perception involves the ‘direct pickup’ of information about the environment in the ambient light. The optic array can be seen as an external information-bearing structure. It carries information about the environment and it exists independently of perceiving organisms. Gibson’s emphasis is on action to explain how a perceiving organism is able to make the information contained in the optic array available to it. Vehicle externalists extend these Gibsonian insights to conscious experience. The most detailed and most influential version of vehicle externalism about perceptual consciousness is offered by the so-called Sensorimotor Con- 26 Johan Veldeman tingency theory of perceptual consciousness (SMC theory, for short), proposed by Kevin O’Regan and Alva Noë, which holds that “vision is a mode of exploration of the world that is mediated by knowledge of […] sensorimotor contingencies” [O’Regan & Noë (2001a), p. 940]. The ‘sensorimotor contingencies’ involved in perceptual experience are the laws that link the perceiver’s actions to the changes in sensory inputs that these actions cause. There are two parts to the SMC theory. The first is that perception is a way of ‘acting’, a kind of skilful activity on the part of the animal as a whole. The second claim is that the ability to perceive is constituted by the possession of the relevant sort of sensorimotor knowledge. Perceiving is taken to be an organism’s exploration of the environment that is mediated by knowledge, or ‘mastery’, of sensorimotor dependency relations. With any exploratory movement that the perceiver makes, she has knowledge about how input will change. There are in fact two versions of the theory. The initial target paper of O’Regan & Noë presents a reductionistic version of the SMC theory, which proposes an explanation of perceptual consciousness in broadly functionalist terms. Later, in Action in Perception, Alva Noë presents a significantly different, non-reductionistic version of it, to which I shall return in the next section. In the initial version of the SMC theory, the laws of sensorimotor dependency are characterised in terms of lower-level patterns of change in sensory stimulation. The immediate problem for this account is that the information used in the fine-tuned visual control of action is in general remote from consciousness.3 The precise details of the exercise of our mastery of sensorimotor contingencies may have no impact on the qualitative nature of our visual experience. Therefore, in order to account for consciousness, the theory has to be supplemented. As such, O’Regan & Noë state the additional requirement that for a creature to possess visual awareness, the exercise of the mastery of sensorimotor contingencies must be used “for the purposes of thought and planning” [O’Regan & Noë (2001a), p. 944]. Furthermore:

[T]o be perceptually aware of an object is not only to interact with it in ways drawing on knowledge of sensorimotor contingencies, it is to make use of one’s skillful interaction for guiding behaviour and other forms of thought and action (such as speech). This amounts to the requirement that, to actually visually experience an item, to see it, one must have a kind of higher-order control of one’s tracking activity. This kind of control […] is a functionally describable capacity [O’Regan & Noë (2001b), p. 1012].

Thus O’Regan & Noë hold that actually visually experiencing an item requires that one has a kind of ‘higher-order control of one’s tracking activity’. The exercise of the mastery of sensorimotor contingencies accounts for phenomenal character which can exist on its own independently of consciousness. Some lower-level perceptual experience is posited that has phenomenal character Varieties Of Phenomenal Externalism 27 on its own, and which can exist independently of conscious awareness. Then, some kind of higher-order representation is invoked to determine whether the experience is conscious or not. As such, visual consciousness is explained in functionalist terms, that is, in terms of cognition. Consciousness is simply taken to be an inner process. Note that, in this regard, the global picture is strikingly similar to the representationalist view presented in the previous section.

IV. FROM ‘PERCEPTUAL EXPERIENCE’ TO MIND:DIRECT REALISM

Neither content externalism nor vehicle externalism supports externalism about consciousness. The alternative route that leads to a robust type of externalism is the view which I shall call ‘direct realism’. This is the view that perceptual experience is, quite literally, a relation between perceiver and environment. Direct realism is committed to what is known as a disjunctivist conception of perceptual experience, which proposes to characterise the subjective character of experience without reference to internal common factors between veridical and hallucinatory experiences [See Langsam (1997), McDowell (1986) and Child (1994)]. One may resist disjunctivism on the basis of the assumption that perception is a causal concept. A perceptual experience and its corresponding hallucination may have the same immediate cause: they are both caused by the same stimulation of some region of the visual cortex. Yet the core idea of direct realism is that seeing does not involve two separate states of affairs that could be regarded as cause and effect, that is, the presence of an object and the experience the subject has in seeing the object. Rather, the experience is a single state of affairs, with the object as a component. Disjunctivism does not deny that perception is a causal concept as such. Rather, what it denies is that causation is a relation between a world-independent experience and something in the world beyond that experience. If a perception is properly understood as the instantiation of a relation, then my brain state is merely a part of the process that constitutes my seeing. A genuine direct realist approach to consciousness has been proposed by John Campbell. Conscious experience, according to Campbell, should explain the knowledge of which thing you are thinking about, or, as he calls it, knowledge of the reference of a demonstrative. The central idea is that “consciousness of objects is what provides knowledge of reference” [Campbell (2002), p. 1]. Knowledge of the reference of a demonstrative involves a kind of non-propositional, epistemic ‘acquaintance’ with particular, categorical objects and properties in the environment. The function of consciousness, according to Campbell, is to provide us with such a non-descriptive cognitive relation to particular objects. According to Campbell, conscious perception is a simple relation between perceiver and object which explains that we can think about the object. 28 Johan Veldeman

According to Campbell, “the qualitative character of the experience is constituted by the qualitative character of the scene perceived” [Campbell (2002), p. 114]. This accommodates the direct realist intuition that perceptual experiences seem to be directly about their objects. Yet Campbell’s account seems to have something amiss. It is undeniable that we are acquainted with the objects of perceptions through their appearances. It is hard to understand what it means to consciously experience a ‘categorical object’ in terms of a simple relation between perceiver and object. Our perceptions are not simply objective recordings of the world as it actually is. It should be noted that direct realism does not require the assumption that phenomenal properties are intrinsic properties of material objects; it may acknowledge that experiences essentially involve appearances of things. Direct realism would be violated only if the way in which an object is being perceived by the subject is characterised independently of whether the object exists. A theory of perception should do justice to both its phenomenal character and the idea that ordinary spatiotemporal particulars such as tomatoes and chairs are given in experience. Campbell’s proposal only seems to do justice to the latter idea. This may invite us to look in the direction of the ‘non-reductionist’ version of the SMC theory, proposed by Alva Noë in his Action in Perception. I call this version non-reductionist, because it is no longer intended as an explanation of phenomenal consciousness. Noë writes:

[The reductionist version of the SMC theory] insisted on characterizing laws of sensorimotor contingency in terms of patterns of change in sensory stimulation rather than in terms of changes in sensation or appearance. Only such a physi- calistic characterization can hope to serve as a ground for a theory of consciousness. […] The main problem with this strategy, I now believe, is that we purchased noncircularity and explanatory power at the expense of giving up phenomenal aptness. A creature enjoys phenomenally conscious perceptual states when it has knowledge of the relevant patterns of dependence of neural activity on movement. But how can phenomenally unconscious states of this sort be the basis of phenomenal consciousness? [Noë (2004), pp. 228-29].

In Noë’s non-reductionist version, the proposal to understand the content of perceptual experience in terms of the perceiver’s mastery of sensorimotor dependency relations is now invoked to elucidate the phenomenology of perceptual experience. The central theme in Noë’s book is the idea that perceptual experience has a dual content. Noë insists that perceptual experience simultaneously involves ‘factual’ content and ‘perspectival’ content [See Noë (2004), Chapter 5]. There is a factual, world-referring aspect of perceptual content, that is, the way experience represents the world as being. And there is a perspectival aspect, which does not merely depend on how things are, but also on one’s relation to how things are. For example, a circular plate viewed from an angle looks elliptical to you, but nonetheless you experience it as Varieties Of Phenomenal Externalism 29 round. In actively encountering the way in which the perspectival shape of the plate varies with your movement, you experience the plate as circular. You see it both ways at the same time. Another example is colour constancy. As perceivers we implicitly understand the way apparent colours of objects vary as we move with respect to them, and this constitutes our experience of uniformity of colour despite its variable appearance. Noë holds that perception has a dual content because perceiving is a practical skill which essentially involves sensorimotor knowledge, such as knowing, implicitly and practically, that had things been different, they would have looked different, and that had one moved, things would have looked different. And the possession of such knowledge accounts for what is known as ‘perceptual presence’: you may experience a chair as visually com- pletely present, even though parts of it are blocked by the table; or you may visually experience a tomato as a ‘whole’, opaque material object, even though you merely see its facing surface. It is an essential part of the phenomenology of perceptual experience that we have a feeling of presence of features of which we are not strictly aware, like the unattended features of the scene before us, unattended environmental detail, and the far sides and oc- cluded portions of the objects before us. Noë makes the analogy with touch. When you hold a bottle in your hand with your eyes shut, you make contact with the bottle at isolated points where the bottle touches your skin. Nevertheless, it seems to you as if the whole bottle is present to your awareness, as if you perceive the whole bottle [Noë (2004), p. 60]. And this is so because the bottle is an external structure that carries information over and above that present in any sensory representation: it provides a stable structure that can be explored at will. And this is true of perception in general: the phenomenology of perceptual experience involves content that is present only ‘virtually’, in the sense that you have some direct, continuous access to it.4 And the ground of this accessibility is our possession of sensorimotor skills, that is, our practical knowledge of how to bring unperceived items into view by movements of the body. Note that Noë’s dual-content view diverges significantly from the initial SMC theory, in a way that renders it compatible with direct realism. The dual content of perceptual experience is elucidated in experiential terms. As such, visual consciousness may play a role in supplying the information about the presence of the particular objects one needs in order to identify them, to think about them, and to reach and grasp them. The initial, reductionist version of the SMC theory gives no such role to conscious experience: the laws of sensorimotor dependency are characterised in physicalist terms, and the practical knowledge of such patterns is characterised in functionalist terms. Within the dual-content view, by contrast, the mastery of sensorimotor dependency relations is taken to involve one’s understanding of the relation between how things are and how their appearances or looks change as one moves. 30 Johan Veldeman

The dual-content view shows how direct realism may be compatible with the idea that the perception of the world is mediated by appearances. While seeing the circularity of the plate in its apparently elliptical shape, or seeing the uniform colour in the differently illuminated parts of an object, neither aspect of the experience has priority over the other. And the perspectival part of the component experience is clearly not identified with context- independent, sensory content: it involves the ways things appear from a certain viewpoint, such as the variable apparent appearances of colours, shapes and sizes. Unlike purely sensory content, the perspectival content of experience outstrips what is given to the eye or brain through sensory causal inputs; it is as much a part of the world as the factual content is. As such the dual- content view may be seen as a plausible attempt to reconcile direct realism with phenomenal facts about experience.

V. CONCLUSION

To argue for externalism on the basis of the external determination (content externalism) or the external location (vehicle externalism) of mental representations is unsupported. Both types of externalism understand phenomenal character as a property of a certain class of mental states that cuts across the conscious/unconscious distinction. Perceptual consciousness, how- ever, is not a property of mental states at all but, rather, a relation between a perceiver and the environment. To acknowledge this is not tantamount to de- nying the phenomenal facts about experience: it is compatible with Alva Noë’s dual-content view on perception.5

Department of Philosophy University of Antwerp Prinsstraat 13 B-2000 Antwerpen, Belgium E-mail: [email protected]

NOTES

1 Dretske writes: “There is nothing in the content of the representation, nothing the representation says, which makes it about this object rather than that object or no object at all” [Dretske (1995a), p. 24]. 2 Campbell (2002), pp. 124-26 and Child (1994), p. 147 make this point. 3 This is suggested by the two-visual-systems hypothesis by David Milner and Melvyn Goodale (1995), which holds that there are two distinct visual capacities, conscious seeing, on the one hand, and vision for the guidance of action, on the other hand. Varieties Of Phenomenal Externalism 31

4 See Noë (2004), pp. 215-17, for a defense of the idea that the content of perceptual experience is virtual. 5 The author gratefully acknowledges The Research Foundation of Flanders (Fonds voor Wetenschappelijk Onderzoek – Vlaanderen) for support during the writ- ing of this paper.

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