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Challenges to Cartesian

materialism:

Understanding

consciousness, naturalism

and the mind-world relation

Jonathan Knowles http://www.academia.edu/2651043/Challenging_Cartesian_Materialism_Under

standing_Naturalism_and_the_Mind-World_Relation

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Overview

• Descartes and the problem of mind in a physical world

• Overview of different contemporary responses to the ’hard

problem’ of consciousness

• Cartesian materialism (CM)

• Why challenge CM?

• Enactivism

• Problems for enactivism

• A non-reductive approach to consciouness

• A neo-pragmatist metaphilosophy

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Descartes on Mind and Matter

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Central problem in the philosophy

of mind since Descartes

• How does the mental fit into a physical world?

• Focus on consciousness. Core of problem here derives from two conflicting intuitions:

• A) Our concepts of consciousness and matter seem distinct:

– I can ‘think away’ everything but conscious thought from the nature of myself, therefore mind and body are substantially distinct (Descartes).

– We can imagine creatures physically just like us and behaving just as we do, but with different conscious experience (‘inverted spectra’) or with no conscious experience at all: ‘Zombies’ (David Chalmers). Assuming these thought experiments are genuine guides to possibility, consciousness properties ≠ physical properties, seemingly.

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David Chalmers, ANU, author

of ’The Conscious Mind’ (OUP

1996)

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On the other hand…

• B) Everything in the world has a sufficient physical cause, including our actions (‘the completeness of physics’). So either conscious events (having a pain, seeing red, hearing music) are identical with or somehow realised in physical causes (contra the Zombie Argument), or they are epiphenomenal. But the latter seems absurd, for surely it is my pain that makes me jump.

• So we have a paradox/puzzle, sometimes expressed as the ‘hard problem’ of consciousness: why does anything physical feel a certain way.

• Elicits a range of different responses in contemporary philosophy of mind. A philosophical paradigm!

• Most retain the belief, in light of advances in the cognitive and neuro- sciences, that the conscious mind is somehow physical and realised in the brain.

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Classical cognitive science

(1950s-) • Accepts that everything mental supervenes on the physical/neural as at

least a working hypothesis.

• Focus originally on capacities involving inference/reasoning/thinking e.g. language production/understanding, early visual processing, solving mathematical problems etc. Now Descartes also thought reasoning was non-physical, since creative/non-mechanical. But modern computer science (cf. esp. Turing) has shown that we can reduce many kinds of intellectual problem to computational problems which can be realised in a physical device.

• Leads to central metaphor of CCS: brain = computer, where neurons etc. are hardware, and reasoning, planning, perceiving etc. are programmes run on this. Data structures = internal representations, with contents fixed by relations to ovjects/properties in the external world

• More integration with neuroscience in recent years, cf. e.g. Bechtel.

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Some recent theories about

consciousness within CCS

• Consciousness is a kind of higher-order representation

(Rosenthal, Carruthers)

• Consciousness is a special kind of first order representation of

the world/body (Tye, Dretske)

• Consciousness is a higher level (functional) neural property, e.g.

informational integration (e.g. Baars, Tononi).

• Consciousness is a special first-order neural property

(’biological theory’, Block)

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More radical gambits

• We can never understand how the brain gives rise to consciousness,

though there is an answer (’Mysterianism’, e.g. McGinn).

• Panpsychism/property dualism: mentality/consciousness is part of the very

fabric of physical reality. Animal consciousness involves a special

organisation of physical stuff already endowed with protopsychic properties,

or is a special ’force’ in the brain needed to collapse the wave function

(Chalmers).

• Consciousness is epiphenomenal (Jackson).

• There is no hard problem, the idea that there is arises from mixing up the

third and first person perspective.

• Scepticism about a special ’what it’s like’ category and an inner ’Cartesian

theatre’ where this is all inspected by ’the mind’, e.g. Dennett. All we have

is what people tell us about what they perceive/experience, and our job as

researchers is to find out what the real mechanisms are in a way that

explains why people report what they do, but also how they behave in

experimental settings.

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Cartesian materialism (CM)

• What all these (more or less) accept is that conscious

experience is a real phenomenon identical to,

realised in or somehow produced by complex brain

states/processes.

• Instead of a dualism of mind and matter we have a

dualism of brain and body/environment: Cartesian

materialism.

• As far as my consciousness is concerned, I could be

a ’brain in a vat’…

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Brain in a vat…

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Challenging CM

• Why do it? Isn’t philosophy/science just hard?

• The very terms of the ’hard problem’ of consciousness seem set up to make it

unsolvable (Evan Thompson, Mind in Life). At least there is absolutely no

consensus on how to make progress on it.

• Why believe the brain is the seat of consciousness? Is this more than a dogma?

If it isn’t, there is arguably no clear demaraction in physical reality between the

realms of the conscious and the non-conscious, in which case, why think that

understanding physical reality will yield an understanding of consciousness?

• One can raise questions about the prevailing methodology/explanatory

assumptions of classical cognitive science/philosophy of mind: notions of

function/behaviour/reference/anything physicalistically respectable given, whilst

phenomenology, ’what it is like’, is to be explained.

• So good motivations exist for questioning CM exist. But how, concretely, should

we provide a better understanding? Can we do so, and in a way that is

recognizably naturalistic/scientific?

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Enactivism about conscious

experience • Enactivism part of a complex and many-faceted movement or set of movements

within recent cognitive science, often known as ’4e’, that opposes CCS:

• 4e: Cognition is embedded, embodied, enacted, and extended (cf. Andy Clark, Susan

Hurley, Rodney Brooks, Evan Thompson, Mark Rowlands, Dan Hutto, Tony Chemero

et al.). Meant to be ’anti-Cartesian’, though controversial as to how and to what

extent. Common denominator is that intelligence/mentality needs to be explained

much more contextually and that this will diminish (at least, alter) the role played by

internal representations and the brain.

• Our focus: Enactivism as developed by Alva Noë and Kevin O’Regan: Heavily

influenced by the phenomenologists, esp. Husserl and Merleau-Ponty. Perceptual

experience is an extended temporal process involving dynamic interaction with the

environment, undergirded by implicit knowledge of sensorimotor contingencies

(’laws’). We need to think of vision as more like touch and less like taking a snapshot

of the world. This will help solve/dissolve the hard problem.

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Noë and O’Regan, ’Senorimotor

account of visual consciousness’

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Experience is not like this…

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More like this…?

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What visual experience is like

according to O’Regan/Noë…

• Dennett agrees with the negative point, but then argues that the richness of experience is an illusion.

• Others say that we/our brain builds up an internal picture from ‘snapshots’ of it together with top-down inferences.

• O’Regan/Noë: Visual experience of the world as evenly and richly detailed is not an illusion but is due to the fact that the world itself is rich and we are able to visually sample it through action (or know we can).

• Visual experience is not something that happens to us, a representation, in the brain. It is an enacted process, something we do, that involves body and world. Somehow this (helps) to solve the hard problem of consciousness.

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Some more empirical

evidence • Change/inattention blindness: We are not good at noticing

features of our visual scenes that are not relevant to our practical projects:

– http://nivea.psycho.univ-paris5.fr/ECS/bagchangeNoflick.gif

– http://nivea.psycho.univ-paris5.fr/ECS/kayakflick.gif

– http://nivea.psycho.univ-paris5.fr/ECS/dottedline.gif

• Knowledge of sensorimotor contingencies: Tactile visual sensory substitution systems recreate phenomenology of vision.

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Assessing enactivism:

empirical problems

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Assessing enactivism:

principled problems • Core ideas behind enactivism: Perceptual experience is ’determined’

by sensation, action, the external world and knowledge of

sensorimotor contingencies.

• But even if this is right, why should any of this feel a particular way

(’the hard problem’)? Does it make sense to suppose the external

world ’feels’ at all? And if all the feeling drains down to the

sensations, which are assumed to be neural, where is the advance

on CM?

• It seems it can’t be true that I need to act to see, but only to know

what would happen if I did. Does knowledge feel any particular way?

Can’t it in any case be realised in the brain?

• Enactivism per se doesn’t seem to go far enough in ’regestalting’ our

thinking about consciousness.

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What we need to

acknowledge… • Consciousness is essentially a person- or organism-level

phenomenomenon. It makes no literal sense to say that my brain sees

or feels this, that or the other. But nor is it any better to think of

experience as being in objects in the external world. Thinking there is a

good question of where experiences are to be found is simply a

’category mistake’ – pace Noë: ‘[W]e are looking for consciousness in the

wrong place if we look for it in the brain.’ (Out of Our Heads, p. 65).

• Consciousness is as such fundamentally intentional: a matter of having

the (or a) world presented/revealed to one. It is only to a subject of

experience that attributions of consciousness make sense, and this

involves attributing it an apprehension of a world.

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What we need to

acknowledge-2… • Phenomenological analysis (Brentano, Husserl, Heidegger, Merleau-Ponty, Sartre) therefore

can indeed must contribute directly to any science of consciousness. Phenomenology is a

first-personal form of analysis but is not a matter of introspection, but rather of detailing the

structure of lived, embodied experience involving inter alia our direct contact with wordly

objects (though conceived of independently of theoreticall assumptions about their

underlying physical nature). Phenomenology thereby aims to reveal the principles

underlying conscious experience qua the lived, experienced world.

• In seeing consciousness as something neither in the head nor in the physical world, the

assumptions driving the ’hard problem of consciousness’ are obviated and the usual debate

not joined.

• A naturalist should however reject the traditional transcendental/aprioristic/idealistic

conception of phenomenology. But this is compatible with the primacy of phenomenological

analysis in the study of consciousness. Together with input from empirical studies and

indeed an understanding of the brain, we can in this way make progress towards a scientific

understanding of consciousness – one that will be able to mesh with the insights and

general approach of enactivism, freed of its reductive ambitions.

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Does this really solve the

problem? • Does this really change anything with respect to the hard problem

of consciousness? Don’t we still have to face up to the fact that at

some point in the history of living things consciousness sprang up

out of purely physical processes? And isn’t this still a huge mystery,

and the central explanandum?

• Yes and no: our anti-reductive account provides a new way of

thinking about consciousness science, one that may also mesh

with fundamental thinking about the logic of life and the idea that

life/consciousness is an emergent phenomenon (cf.

Varela/Maturana/Thompson on autopoiesis).

• OTOH we are still left with a question about how life emerges from

the primordial slime, what it is to be thus emergent etc.…

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Neo-pragmatism

(Kuhn/Rorty/Price) needed too • Think of our predicament in terms of our having on our hands two broad but

incommensurable discourses: the discourse of fundamental physics/physical

processes on the one hand, and the discourse of experience/the lived world/life

on the other. There will of course be – there are – connections/overlaps between

the discourses, and our knowledge as a whole must aim for a certain overall

coherence. But we do need to see the discourses as ideally fitting in to one all-

inclusive story about ’reality’?

• Cp. Nils Bohr: ’There is no quantum world. There is only an abstract quantum physical

description. It is wrong to think that the task of physics is to find out how nature is.

Physics concerns what we can say about nature.’

• I agree, but do we even need the category of nature/reality?

• Being a neo-pragmatist is arguably good practice in science generally, as well

as, arguably, being the only viable response to the age-old epistemological

problems of philosophy.