Challenges to Cartesian materialism: Understanding consciousness, - PowerPoint PPT Presentation

1 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

2 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

3 Descartes on Mind and Matter

4 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.

5 David Chalmers, ANU, author of ’The Conscious Mind’ (OUP 1996)

6 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.

7 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.

8 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)

9 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.

10 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’…

11 Brain in a vat…

12 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?

13 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.

14 Noë and O’Regan, ’Senorimotor account of visual consciousness’

15 Experience is not like this…

16 More like this…?

17 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.

18 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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20 Assessing enactivism: empirical problems