3.4.2 Dualist Theories - 12 markers Flashcards
(9 cards)
Explain Descartes’ conceivability argument for substance dualism and the response that what is metaphysically possible tells us nothing about the actual world.
Substance dualism is the theory of mind that claims that the mind and body are not identical, and that they are in fact two entirely different “substances”. The mind is a “thinking thing” which is non extended (does not take up space), and the body (like all physical things) is an “extended things” which does not think.
Descartes’ conceivability argument for substance dualism can be put formally:
P1: It is conceivable for my mind to exist without my body.
P2: If it is conceivable for one thing to exist without another, then it is metaphysically possible for one to exist without another.
C1: Therefore it is metaphysically possible for my mind to exist without my body.
P3: If it is metaphysically possible for one thing to exist without another, they are not identical.
C2: Therefore, my mind is not identical with my body.
This conceivability argument can be criticised by attacking premise 3 “If it is metaphysically possible for one thing to exist without another, then they are not identical”, arguing that what is metaphysically possible tells us nothing about the actual world.
By Descartes reasoning it follows that these two propositions are incompatible: (1) My mind is my brain (2) There is a possible world where my mind exists but the brain does not.
Churchland argues that this type of reasoning puts an absurdly high standard on any possible scientific reduction. Scientists need only to focus explaining scientific relations in the actual world (not what is going on in other possible worlds). If this standard was placed on scientific reductions, such as water to H20, we not be able to say these are genuine identities either.
Explain Descartes’ indivisibility argument for substance dualism and the response that not everything thought of as physical is divisible.
Substance dualism is the theory of mind that claims that the mind and body are not identical, and that they are in fact two entirely different “substances”. The mind is a “thinking thing” which is non extended (does not take up space), and the body (like all physical things) is an “extended things” which does not think.
Descartes’ “indivisibility argument” for substance dualism goes as follows:
P1: All physical things are divisible
P2: The mind is not divisible
C1: Therefore, the mind is not a physical thing.
The indivisibility argument can be criticised by attacking premise 1 - ‘All physical things are divisible’, arguing that not everything thought of as physical is divisible. This remains a question of whether there are physical things that cannot be divided in principle. Take the example of a force field, if I were to divide a force field, I would be left with half a force field – in which I cannot. As this would change a fundamental part of our physical universe.
Explain interactionist dualism and the empirical interaction problem facing it
Interactionism is the theory that the mind and brain causally interact with each other. Interactionist dualists believe that events caused in the brain can cause things to happen in the mind, and that events in the mind can cause things to happen in the brain.
This can be illustrated with a story of burning your finger on a hot pan involving both physical and mental things interacting in a causal sequence:
I burn my finger on a hot pan. this causes nerve signals to travel to my brain, where C-fibres fire (Physical-to-Physical causation). The firing of C-fibres cause me to feel intense pain in my finger (Physical-to-mental causation). The feeling of pain makes we want to move my finger away from whatever burned me (Physical-to-mental causation). My desire to move my fingers causes motor neurones in my brain to fire (Mental-to-Physical causation) The motor neurones cause my arm to move away from the hot pan (Physical-to-Physical causation).
Interactionist dualism can be criticised by the empirical interaction problem for being incompatible with physics.
The empirical interaction problem can be put formally:
P1: If interactionism was true, we would need to reject a fundamental principle of physics (the conservation of energy).
P2: We should only reject a fundamental principle of physics if there is extremely good empirical evidence of it being violated.
P3: There is no empirical evidence of the conservation of energy being violated in brains.
C1: Therefore, interactionism is not true.
Explain the philosophical zombie argument and the response that what is conceivable may not be metaphysically possible
A philosophical zombie is a hypothetical being that is physically identical to a normal, conscious human but lack phenomenal consciousness. Chalmers uses the idea of philosophical zombies to argue against physicalism by showing that phenomenal consciousness does not supervene on physical states.
The Zombie argument can be put formally:
P1: Philosophical zombies are conceivable.
P2: If philosophical zombies are conceivable, they are metaphysically possible.
P3: If philosophical zombies are metaphysically possible, then phenomenal consciousness does not supervene on the physical.
C1: Therefore, phenomenal consciousness does not supervene on the physical.
In response, the zombie argument can be criticized by attacking P2 “ If philosophical zombies are conceivable, they are metaphysical possible”, arguing that what is conceivable does not imply metaphysical possibility. In the 1850s, scientists could conceive of water existing in a universe where H2O did not exist – even though such a situation was metaphysically possible. Perhaps the sentence “pain is firing C-fibers” in the early 21st century is like “water is H20” In the mid 19th century: necessarily true, even though we can conceive of it being false.
Explain the philosophical zombie argument and the response that philosophical zombies are inconceivable
A philosophical zombie is a hypothetical being that is physically identical to a normal, conscious human but lack phenomenal consciousness. Chalmers uses the idea of philosophical zombies to argue against physicalism by showing that phenomenal consciousness does not supervene on physical states.
The Zombie argument can be put formally:
P1: Philosophical zombies are conceivable.
P2: If philosophical zombies are conceivable, they are metaphysically possible.
P3: If philosophical zombies are metaphysically possible, then phenomenal consciousness does not supervene on the physical.
C1: Therefore, phenomenal consciousness does not supervene on the physical.
The zombie argument can be criticised by attacking P1 “Philosophical zombies are conceivable,” arguing that zombies are not conceivable. Dennett argues that it is not possible to imagine having a conversation with a philosophical zombie where you talked about deeply held feelings i.e. hopes, fears, desires for the future etc. Unlike you, it would simply be an automaton creating sequences of sounds and facial expressions with no awareness at all. You would notice something off with their behaviour.
Outline Jackson’s/”Mary” argument (for property dualism) and the response that Mary gains acquaintance knowledge rather than propositional knowledge.
Property dualism is a dualist theory of mind that claims that there are alteast some mental properties that are neither reducible to nor supervenient upon physical properties.
Jackson’s knowledge argument for property dualism can be put formally:
P1: Mary knows all the physical facts
P2: When she leaves the room, Mary learns a new facts
C1: Therefore, before she left the room, Mary did not know all facts
C2: Therefore, there are non-physical facts
P3: If there are non-physical facts there are non-physical things
C3: Therefore, there are non-physical things
The knowledge argument could be criticised by attacking P2 “When she leave the room, Mary learns a new fact”, arguing that Mary gains only acquaintance knowledge, not propositional knowledge. Mary does not learn new facts, but she “gets to know” redness.
Explain the “problem of other minds” facing dualism and the response that the existence of other minds is the best hypothesis.
Cartesian dualism holds that minds exist, and that they are not identical to bodies. This means that minds do not depend on bodies to exist.
The argument for the “problem of other minds” can be put formally as such:
P1: If dualism is correct then I have direct access to my own mental states but not to those of
others.
P2: All I can know of others is their behaviour (and even this is not known directly, but via my
mental representations of the external world).
P3: However, I am not in a position to know that any behaviours I observe are caused by mental states in others because (a) the relationship between a mental state and a behaviour is contingent; and (b) there is no epistemological route for me to the non-physical states of others.
C1: Therefore, I am unable to know that there are other minds than my own.
Descartes would respond using the “best hypothesis” argument. Descartes argues that there are two differences between to humans (with minds), and machines (without minds). Firstly, humans use language, it is inconceivable for a machine to answer questions meaningfully, so our use of language shows that we have a mind while machines do not. Secondly, humans are capable of highly adaptable behaviour, while machines lack adaptability. If machines had genuine intelligence, there would be no such asymmetry. So existence of other minds explains these two things best.
Outline epiphenomemalist dualism and explain the challenge posed by introspective knowledge
Epiphenomenalism is a dualist theory of causation that claims that (a) mental states exist (b) they are caused by physical things and (c) they are causally inert i.e. they have no causal effect on on the physical or mental.
If epiphenomenalism is true, introspective self-knowledge is impossible. However, this means that I cannot possibly know that I am in pain because my pain does not cause anything, it has no effects. If my pain does not cause anything then it is impossible for my pain to cause me to believe (and so to know) that I am in pain.
Outline Jackson’s ‘knowledge/Mary’ argument, as well as the ‘New Knowledge/Old Fact’ response
Jacksons ‘knowledge/Mary’ argument can be put formally as such:
P1: Mary knows all the physical facts
P2: When Mary leaves the room, she learns a new fact
C1: Therefore, before she left the room, Mary did not know all facts
C2: Therefore, there are non-physical facts
P3: Physicalism claims that all facts are physical facts
C3: Therefore, physicalism is false
The knowledge argument could be criticised by attacking P2:”When Mary leaves the room, she learns a new fact” arguing that Mary gains new knowledge, but this is knowledge of an old fact. Before leaving the room, Mary knows that red perception = certain brain states. After leaving the room, Mary does not learn a new fact about red, just a different way of knowing the same fact that red colour perception = red qualia.
