The Appearance of Reality

Presentation for Boston Philosophy of Mind 2/27/10, Boston, MA

Thomas W. ClarkCenter for Naturalism

Naturalism.Org

Overview Preliminaries: the hard problem and naturalism Epistemic perspectivalism and a conclusion

about mental causation. Options for explaining consciousness. Motivating representationalism. The mental-physical distinction as a

representational phenomenon. How representationalism might help solve the

hard problem. What epistemic perspectivalism might explain.

Generating the hard problem

Mental realism: reality of qualitative, private subjective states, billions of them, that aren’t publicly observable. Implausible alternative: eliminativism.

Physical realism: reality of public, self-existent objective world that we access via consciousness, which contains billions of loci of subjectivity. Implausible alternatives: idealism, solipsism.

Explanatory gap: seeming incommensurability of the mental and physical in current philo-scientific theory, the collaboration of philosophy and science. In explaining consciousness we’re engaging in the collective, intersubjective philo-scientific enterprise that more or less assumes the existence of physical, self-existent, mind-independent objects. Hence the bias toward physicalist reduction.

Target properties of consciousness: the appearance of a unified phenomenal world composed of elementary qualia – pain, red, etc. – with the subject at its center; essentially private, qualitative, ineffable, unified, and intentional - carrying information.

Naturalism Rational epistemic commitment to intersubjective

empiricism, exemplified by science, when modeling reality. The argument from objectivity: in seeking objectivity, must

minimize subjective bias, hence must use intersubjective evidence available in principle to all observers.

Non-dualism: scientific empiricism tends to unify our understanding of reality.

No intersubjective evidence for soul, supernatural, or paranormal.

Naturalism nothing new: precursors, long history. Explanatory success of science adds plausibility to

naturalism.

1a. Epistemic perspectivalism Epistemic perspectivalism – a representational thesis.

Reality is only known under a description, as modeled by a representational system (RS) with a limited perspective; reality is never grasped directly. Reality appears for a system (hence the title of this presentation) by virtue of the system’s representational, knowledge-gathering (epistemic) capacities.

Mental-physical distinction (MPD) is a function of representation. For a knowledge-seeking representational system, the mental is what the system categorizes as its own internal representational operations, plus the self which produces or possesses them. The physical is what’s categorized as external reality, both directly presented and as represented by internal operations. Note that the system isn’t specified as mental or physical! (see part 4)

Epistemic perspectivalism, cont. Epistemic categorization becomes ontological

dualism. Folk metaphysics takes a naively realist view of the MPD - we’ve divided reality into two substances. We are mental and physical realists (see start of presentation). Philoscience inherits this dualism, then wants to overcome it.

The hard problem is how to put reality back together. We’re stuck inside our categories with the Memphis blues again. Watch out for epistemic and explanatory loops! Is there a way out? Maybe the concept of representation – prior to the MPD – is the key. But in conceiving representation we can’t help but assume the MPD. Can you see the way out? Help wanted!

Meanwhile…

Epistemic perspectivalism, cont. Two epistemic perspectives (EPs). Organismic perspective,

results in 1st person qualitative subjective consciousness, vs. the 3rd person intersubjective perspective, results in quantitative and conceptual scientific theory. Each has its own basic representational vocabulary, one qualitative, the other quantitative/conceptual.

1st person subjective epistemic perspective. The organism/system (e.g., human) has complex representational capacities, in our case acquired via evolution, which somehow entail phenomenal, qualitative consciousness – a subjective mental reality. Consciousness is categorically private: experiences are always someone’s, tied to particular representational systems (RSs);

3rd person intersubjective epistemic perspective. Public, objective, scientific models of reality abstract away from qualitative subjective experience in forming conceptual and quantitative descriptions of the world. Qualia necessarily drop out when forming concepts and constructing quantitative and causal models in the collective epistemic perspective we call science. (Ray Tallis quote in notes).

Epistemic perspectivalism, cont. David Gamez on the two perspectives as non-interacting:

“The approach to consciousness in this thesis is based around the identification of correlations between the phenomenal and physical worlds … which may eventually lead to a causal theory of consciousness. However, until this point is reached it is inappropriate to use phrases like ‘The consciousness of X is caused by brain state Y’ or ‘The brain state Y gives rise to the consciousness of X.’” (from Gamez’ thesis on consciousness)

Human beings occupy both epistemic perspectives. We experience the world, and we conceptualize the world. We feel and we do science. This is why we can talk about (conceptualize) consciousness, not because consciousness causally influences our neurons – more on this later.

1b. The problem of mental causation The problem: How do private conscious mental states

cause physical, intersubjectively observable behavior? Answers:

Physicalism: conscious states just are what the brain does, so no problem. But this violates the privacy constraint on consciousness: we observe brain states, but not experience.

Eliminativism: no mental states, so no problem of mental causation. But it’s tough to give up on mental realism.

Dualist interactionism: problematic since no mechanism specified, conservation of energy violated. Further, EP says qualia in a different explanatory space than the brain.

Epiphenomenalism: mental states exist alongside physical states but are not causally effective. But can I really believe pain plays no causal role in my behavior?

So what’s the solution??

The problem of mental causation, cont. Epistemic perspectivalism (EP) says: it’s a mistake to suppose we

can combine the 1st person subjective, qualitative perspective and the 3rd person intersubjective conceptual-quantitative perspective when explaining behavior. Predictably, we will want to combine them since we occupy both perspectives, and philoscience wants to since it seeks a unified account of reality. But remember:

Experience doesn’t exist from an intersubjective perspective. No one has ever seen or observed an experience. I don’t observe your experience, nor you mine. We only observe the physical correlates of experience; that’s all that’s available to science in its explanations since subjective qualities drop out in concepts and quantities.

So therefore…

The problem of mental causation, cont. Consciousness isn’t even epiphenomenal from the 3rd person EP.

Consciousness doesn’t appear intersubjectively, only subjectively. It doesn’t occupy the same explanatory space as brains, neurons and other publicly available phenomena, so it can’t be epiphenomenal. Each epistemic perspective has its own explanatory space, one qualitative, one conceptual-quantitative. Explanatory spaces can’t causally interact since they are epistemic phenomena. But…

Conscious states are essentially causal from the 1st person EP. We non-inferentially experience pain as the cause of wincing, limping, of learning to avoid painful stimuli.

Since we occupy both EPs, we naturally try to combine them in our explanations of behavior, but fail. We are subjectively certain that pain is causally effective, but can’t conceive of how it affects neurons in 3rd person explanations. Recommendation: stop trying!

2. Options for explaining consciousness What we’re shooting for. We want a satisfying

explanation, one that demonstrates a transparent, intuitive, necessary entailment from 3rd person reality to 1st person reality, closing the explanatory gap, or if that’s not forthcoming, explain what the relation, if any, is.

Standard types of explanatory relations. 3rd person philo-scientific explanations of phenomena usually involve causal, combinatorial or emergentist entailments from less complex to more complex phenomena, but:

Consciousness is essentially private and subjective. Phenomenal states constituting consciousness exist only for a representational system; no conscious states have ever been intersubjectively observed, therefore:

Explanatory options, cont. Not a causal relation: mental/subjective not causally

produced or generated by physical/objective since that would make it public; causal mechanisms are non-starters, e.g., no “2nd transduction” into objective mental stuff (Dennett).

Not a combinatorial relation: no locatable elementary “quanta” or “units” of the phenomenal that get combined into personal consciousness; panpsychism a non-starter. No observational evidence for panpsychism as yet.

Not emergence: emergentist explanations involve part/whole relations, but the parts and wholes are of the same (public) kind, and underlying mechanisms and relations are in principle discoverable/observable; but consciousness not public, no obvious public object relations out of which something categorically private could arise as an emergent phenomenon.

Explanatory options, cont. Not identity: identity claims between private qualitative

experience and public, non-qualitative states of affairs are very difficult to sustain, so physicalism, reductive or non-reductive, is a tough sell, e.g., Jaegwon Kim explores the limits of physicalism here.

Not interactionist dualism: substance dualism supposes consciousness is objective, on the same playing field as physical objects, but this seems wrong according to epistemic perspectivalism (see part 1 above). Interactionism violates causal closure, plus there’s no evidence for the causal contribution of qualia in 3rd person explanations, e.g. no evidence for violations of energy conservation, for instance as hypothesized by Eliztur.

So, what’s left in the way of an explanatory option?

Explanatory options, cont. Conclusion re explaining consciousness. 3rd person

theory needs, ideally, some sort of non-causal, non-combinatorial, non-emergentist entailment to understand how qualitative consciousness comes to exist only for a system that’s part of the natural, physical world.

Possible representational explanation coming from EP: qualia, the basic qualitative elements of conscious mental reality, are non-causally entailed by being a sufficiently recursive and ramified representational system (RS). Phenomenal reality necessarily appears for the RS as a function of what’s involved in adaptive representation (a tentative hypothesis – see section 5 forthcoming).

3. Motivating representationalism Prima facie plausibility of representationalism. Given robust

evidence of correlation with neurally instantiated higher-level representational functions, consciousness is likely an entailment of being a complex representational system (RS), see here for evidence and citations. But the exact nature of that entailment is difficult to specify - the hard problem.

Neural activity sufficient for consciousness. Dreams, especially lucid dreams, are good evidence that brain processes are sufficient for consciousness. No need for online sensory or behavioral interaction with the world for full-blown conscious and self-conscious states to exist (contra Noe in Out of Our Heads).

General claim about self-regulation and self-representation. Having an internal representational self-model is necessary for self-regulation, according to Metzinger, citing Conant and Ashby, 1970, “Every good regulator of a system must be a model of that system.” International Journal of Systems Science 2: 89-97. Reprinted in G. J. Klir, ed., (1991), Facets of System Science. New York: Plenum Press.

Motivating representationalism, cont. Representation as anticipation in service to behavior control.

The brain evolved representational capacities in response to behavior control exigencies. Internal states that track the environment are necessary for flexible behavior that responds to environment under time pressure. Brain is a predictor of events (Jeff Hawkins: On Intelligence), hence needs internal model that anticipates the world, otherwise response time too slow, action too late. Brain looks to confirm/disconfirm currently active model using sensory input. Metzinger: “dreaming vigorously at the world.”

Co-variation of intentional brain states and conscious states. Particular neural sub-systems at various levels, e.g., the visual cortical areas, support particular feature recognition, e.g., colors, edges, movement, faces, objects, binding, highest level gestalts (workspace) – all these are intentional, information-carrying, hence representational systems. We observe close co-variation between certain classes of physically instantiated intentional states and reported phenomenal states, e.g., color, taste, smell, proprioception, plus bound unified gestalts (objects, self, world).

Motivating representationalism, cont. Qualia as 1st person representational content. Subjective

phenomenal states (basic elements are qualia) are plausibly construed as representational, informational, intentional content about the organism and world, content which is normally associated with high level behavior (Tye: Ten Problems of Consciousness, Dretske: Naturalizing the Mind, Lycan: Consciousness, Metzinger Being No One, The Ego Tunnel, Tononi articles, and other representationalist philosophers).

Conclusion re representationalism. Representationalism a plausible, evidence-based hypothesis that connects brain functions and phenomenology. They co-vary closely and both carry intentional, representational content about the world and thus are central to explaining flexible behavior, from both the 3rd and 1st person epistemic perspectives, respectively. But what is the connection, the entailment from 3rd EP to 1st EP, precisely? That’s the hard problem, see part 5.

4. Mental-physical distinction as a representational phenomenon Consciousness as essentially qualitative. Qualitative states,

ordinarily bound into integrated objects, scenes and events with the phenomenal self at the center, are all there is to consciousness. There is no non-qualitative contrast set for qualia within experience. If you subtract all qualitative experience, would there still be something it is like to think, believe, or be the subject of other non-sensory, non-perceptual states?  Arguably not. We never transcend our qualitative states.

The mental-physical distinction is generated within consciousness. Although qualitative experience is all we have as conscious subjects, we pre-theoretically, folk-metaphysically divide the world given to us in experience between what’s mental (my private thoughts, emotions, and sensations that no one else has access to) and what’s physical (my body and brain, other people, external objects, all of which are possible objects of observation by others).

Mental-physical distinction, cont. “Stuck inside of Mobile…”. As conscious subjects we rarely step

outside the MPD categorization of our represented reality: the external world as we represent it usually seems directly given to us as a physical, system-independent reality, and our internal states as we represent them are directly given to us as a mental, system-dependent reality. Moreover, as conscious beings we never step outside our phenomenal, “system-real” worlds – the private representational reality of qualitative experience – within which this categorization is generated. As Metzinger puts it, we're stuck inside our ego tunnels. We never transcend consciousness.

The mental-physical distinction as representational. The mental-physical distinction (MPD) is a represented distinction that gets it content from more basic representational achievements of behaviorally complex representational systems (RSs) such as ourselves. The RS discriminates (represents the difference) between 1) self and world, 2) between what’s inside and outside the system, and 3) between represented states and what’s represented (a representationally recursive achievement). These discriminations have their neural correlates (with which evolution did its work), but are also phenomenally real for us, hence part of commonsense folk metaphysics.

Mental-physical distinction, cont.

Elements of the Represented Mental-Physical Distinction

Mental Physical

Self (soul, mental agent)

Not-self

Internal External

Private Public

Non-spatial, non-extended

Spatial, extended

System dependent System independent

Representation What’s represented

Mental-physical distinction, cont. Naïve realism re the MPD. Folk dualism supposes that we have

direct contact with the external, physical world (including the body) in that some experience is naively classified as being physical: we are thus naïve realists about the external world (Metzinger). We also experience being in direct contact with the mental realm, e.g., our thoughts and emotions, so we are also mental realists, and perhaps naïve in this as well.

The discovery of the hard problem. Philosophy (and then with science, hence “philo-science”) inherits folk dualism, but goes further: according to a widely held theory (as opposed to pre-theoretical commonsense) conscious experience is entirely mental. The theory says that in experience we don’t have direct contact with the physical external world as the naïve realism of folk metaphysics would have it. Instead, consciousness mediates that contact. But where does consciousness itself come from? This is the hard problem.

5. The hard problem: explanatory possibilities of representationalism From a representational categorization to a metaphysical

divide. Philoscience is trying to conceptually unify, by means of a theory, a pretheoretical represented categorization of reality divided into the mental and physical (the mental-physical distinction, MPD). This representational categorization gets construed by folk naïve realism, and then by much traditional philosophy, as a metaphysical claim: that there exist in reality two categorically different sorts of things or substances, mental vs. physical.What connects these two seemingly disparate realms?

Epistemic perspectivalism, round 2: being a representational system as possibly entailing consciousness. The story I favor is representational. Following others who explore representational accounts of consciousness, I suggest that the appearance of a private phenomenal reality for the system – conscious experience – might be entailed by certain of the system’s representational characteristics and capacities. Where I part ways with most others is in denying the causal contribution of consciousness in 3rd person accounts of behavior, as argued in part 1b above.

The hard problem, cont.Some explanatory target properties of consciousness

Qualia: The basic elements of consciousness are irreducibly qualitative (e.g., pain, red), in that they possess an essential character (the redness of red, the painfulness of pain) that itself can’t be further qualified or broken down. This makes such qualities (qualia) ineffable: not amenable to further description.

Unified gestalts: But qualia never appear alone in consciousness (Metzinger), but are grouped into objects, scenes, events, and a coherent experiential gestalt of self-in-the-world.

Phenomenal self: At the center of our phenomenal reality (most of the time) is the phenomenal self, the hard to pin down but very “system real,” qualitative sense of being an experiencer to whom experience is presented.

The hard problem, cont.

Two sorts of considerations about representation, logical and adaptive (mostly from Metzinger):

Logical: what’s possibly entailed by being a representational system independent of adaptive considerations – no selection pressure.

Adaptive: what further characteristics selection pressure might have given a representational system (RS) that might explain consciousness – the existence of phenomenal reality for the RS.

To be continued…

See www.naturalism.org/appearance.htm parts 5 and 6 for the rest.

Thanks!