Assess the claim that mental states cannot be reduced to physical states
By mental states we are referring to ideas, beliefs, emotions and the like. By physical states, we are referring to neuron interaction and connections. Substance Dualists claim that we have a separate mind and brain, where as reductive physicalists state that there is no mind as such – only a brain and brain states. As we shall see, the reductive physicalists provide the most compelling case.
Mental thoughts causing physical movement may seem natural to us at first. If one wishes to go to the cinema, one thinks about going to the cinema first and then physical goes there – a mind seems to think first and cause the brain to carry out the required steps. This is what substance dualists believe, that actions are caused by a separate, non spatial, non physical, mind.
However, although attractive at first, certain problems arise with this view. Such as how can a non physical mind interact with a physical brain? Some philosophers have suggested that they are somehow connected or tethered together. Be that as it may, our actions seem to be very dependent on our brain; more specifically neurons. If one has too much to drink, then one finds thinking and reasoning clouded and movement difficult. One can think of similar examples regarding brain damage. Thus, ones ‘mind’ seems to be dependent on, if not the same as, ones brain.
Occasionalism is a theory which attempts to solve the problem of mind body interaction. It is accepted by this theory, that there is no mental – physical causation. Rather, when one wishes to do something, say buy an ice cream, once one has completed the initial step of thinking about buying an ice cream and goes next to do it, God interferes and makes our hands, mouth, voice box all move and work so that one feels like one’s own mind is controlling one’s physical body.
This argument fails to solve the issue of neural dependency, since one’s ability to think and move is still affected by alcohol etc. One would be forced to conclude that God was also being an ‘internal busybody’, and adjusting the way we walk and talk when one is drunk. Furthermore, God would also have to be interfering with our non physical minds in order to give us the feeling of being drunk. Occasionalism does not mention God doing this, but only that mental thoughts and physical actions should correlate. Is one also forced to believe in a god to accepted substance dualism, and what happens to the mind after the death of the body? Substance dualism thus creates more questions than it can answer – rendering it useless as a philosophical theory.
Logical behaviourism attempts to answer the problem of mind – body interaction by stating that all mental states can be fully reduced to actual or potential behaviour. Human beings can thus be reduced down to beings with, very complex, stimulus response mechanisms. We have a stimulus, a headache, this is then fed into the so called ‘black box’ – the neurons do their thing – and a response is produced: a whimper and a moan. Pain, therefore, is not a private sensation.
Be that as it may, people do not always show signs of pain. Such a criticism was offered by Putnam’s ‘Super Spartans’. This criticism can be answered by the simple stimulus – response mechanism. If two people have the same stimulus, arm being cut off, then just because one of them (the ‘Super Spartan’) shows no outward signs of pain, doesn’t mean they have no behaviour – on the contrary – they would have been disposed to show no pain, a pain behaviour in itself, just like the other person was disposed to show pain. Besides, there are certain biological pain behaviours, such as sweating and increased heart rate, that one cannot control. These dispositions form the basis of behaviourism. For a statement to be true, simply a series of ‘if then’ statements need to be true. Jim believes it is going to rain, if she is going outside, then she will put a coat on; if she has washing outside, then she will bring it inside.
Logical behaviourism also makes the criticism of substance dualism that it has made a ‘category mistake’. Take the example of Oxford University. A friend shows a new comer around the city, at the end the new comer says, “that’s all very nice, but where is the university?” He has not realised that all the different buildings – the colleges, libraries and so forth – are the university. Substance dualists have been guilty of the mistake, trying to find this mysterious ‘mind’, when it fact the mind – behaviour – is all around them.
The problem of the privacy of the mental does seem unsolved however. In order to know how I feel about something I don’t need to understand my behaviour from a third person perspective: I have firsthand knowledge of what I am feeling right now. Although this is true, reflection on behaviour, especially subconscious behaviour, can help us understand exactly how we were feeling and why. Mark, for example, is tired, and Amie is annoying him, Mark shouts at her, in an unreasonable manner, to be quiet. On reflection of his behaviour, mark now understands that he is feeling grumpy. Therefore, this is an argument that a (correct) first person view into one’s own feelings and emotions is not always possible until an analysis of one’s behaviour has taken place.
Furthermore, by accepting that all mental states are just actual or potential behavioural states, the problem of qualia becomes difficult to solve. One can imagine a situation in which a ‘neurological zombie’ has all the same behavioural reactions as other people, but yet not be a person per se, or so we might like to think, yet behaviourists would be forced to conclude it has a consciousness.
The identity theory attempts to fully explain or reduce all mental states to purely physical, brain, ones. The ‘type-type’ theory fails on account of its strict psycho-physical causation law. Although water must always be H2O – brain states such as, but not confined to, pain have to always be the C-fibres firing in the brain. One can imagine that different people and/or different organisms have their pain, or idea, though, emotion, desire etc., caused in different ways. To say then, that “my C-fibres are firing, therefore I am in pain, “may not apply to everyone, and since it is impossible to recreate brain states – especially very complex ones involving multiple thoughts and ideas – how can we ever find out?
The ‘token-token’ theory, however, offers a solution since it states that mental states, such as the feeling of pain, may be multiply realised. A digital watch and an analogue one may both be very different it how they tell the time, but they both do the same thing, namely telling the time – they are thus both ‘timekeepers’.
Qualia is not a problem, despite the thought experiment entitled ‘Mary the neuroscientist’, which aims to prove that the qualitative feel of things cannot be gained from the study of neurones. Whatever Marry sees when she is realised from her black and white prison – say the colour red – this is not new knowledge; for she knew that when she saw red certain neurones would fire and cause this experience she is now having. This isn’t knowledge of two facts, but the same one presented in a different way. Take the example of the characters Dr Jekyll and Mr Hyde from the novel The Mysterious case of Dr Jekyll and Mr Hyde: both are at first understanding different people, but then the reader understands that they are the same person presented in two different ways.
As for intentionality, some identity theorists have pointed to tree rings as evidence to support the conclusion that neurones can be about things. These tree rings contain information about the weather; which vary in a law-like fashion depending on the conditions. Can this purely physical thing exhibit intentionality then? Questions have been raised about whether this is the same as a person’s belief about the weather. But, nevertheless, this is still evidence to prove the identity theory’s conclusion.
Finally, only the identity theory can solve the problem of neural dependency – as the mind being the brain it is inevitable that any alterations to the brain will thus affect our conscious experience. It furthermore solves the mind-body interaction as they are both one and the same; and the privacy of the mental can, in theory, be exposed as no privacy at all: thoughts and desires et cetera being only neurones firing and interacting one could, in theory, with enough understanding of the brain know what someone was thinking.
Overall, only the identity theory has enough credibility for one to accept its conclusions; that the mind and the brain are one and the same. Substance Dualism being stumped on neuronal dependency, mind body interaction and logical behaviourism becoming stuck on, or offering half baked answers to, issues such as privacy of the mental, intentionality and qualia. Only the identity theory can give satisfactory answers to these questions.