Evaluate the Causal Argument for the Identity Theory of the Mind

The second premise holds that every physical event in the world has a physical cause. This is known as the completeness principle but is not intended to be a necessary truth or an analytic truth, and seems more to be an empirical premise. In longhand this premise hold that all physical effects are purely caused by physical prior histories. The thought being in terms on the human mind and body that our physical behaviour will have been fully caused by relaxing or contracting or muscles, which would have been caused by the sending of messages through your nerves, caused in term by activity in your sensory cortex etc. Here the first two premised imply there are two distinct causes that cause physical effects. This introduces the idea of physical effects being overdetermined. Typical examples of overdetermination include events such as someone being shot by a firing squad, or to use Papineau’s example, the idea of someone being shot and struck by lightning at the same time. However, intuitively this seems false. In both examples the effect of the person dying could be caused by either but more importantly cause be caused by one without the existence of the other, ie if the man had not been shot he would stil have been killed by the lightning. In the case of human physical behaviour this implies that without a physical cause the physical effect would still have taken place with just the supposedly sufficient mental cause. This again seems intuitively false, although may have seemed more than reasonable to dualists such as Descartes, as empirically we know that, for example, is a person is, for want of a better expression, brain dead, and has no conscious mind, or physical brain activity, it would be impossible for him to be conscious, and hence have mental events that could cause physical effects. Similarly it seems odd to suggest that I would have, to refer to my previous example, gone to get a drink of water if I had not felt thirsty. Or if I had not felt cold I would not have gone to put another jumper on. Hence we are lead to the third premise of the argument. This premise roughly acknowledges that, to use Papineau’s formulation of this premise: ‘The physical causes of consciousness aren’t always over-determined by distinct causes.’

However, it is possible to refute premise three and claim that there are two distinct causes, which act together (so to speak.) This has been known as the “belt and braces” view, implying a kind of counter-factual dependence between the two concepts. This view avoids errors made in cited in the firing squad example where the implication suggests that there would be the same physical effects if either one of the two sufficient causes took place. Hence the argument manages to avoid the trap on the inevitable theoretical consequences of overdetermination. However, this view fails to fully account of the nature of this counterfactual dependence and cannot answer to the counter argument that there do not seem to be any other natural other incidents of this “belt and braces” mechanism in our world.

Papineau argues that to make premises one to three consistent and plausible we find ourselves set the task of identifying the mental events mentioned in premise one with the physical causes of premise two and in doing such we avoid the notion of overdetermination by proving them to be indistinct. The difficulty of this task has been in active debate as intuitively to some, what it seeks to achieve seems illogical. One of the main arguments is that ‘sensation’ does not mean the same as ‘brain process. To counter this Ullin T. Place pointed out that just because the two concepts do not mean the same thing it does not mean they are not identical. Hence, to site another earlier example, ‘lightning’ does not mean the same as ‘electrical light discharge.’ Fundamentally our means of acquiring the two concepts is different, but this does not prevent ‘lightning’ from being identical to ‘electrical light discharge.’ This adheres to my earlier reference to Feigl and Smart’s response as to the nature of concepts as more of a case of distinguishing the meaning of a concept from its referent. This seems to suffice not only logistically but also, as Smart pointed out, is also the simplest ontology possible. Kim uses the Ockham’s razor test to apply to this response. By this principle entities must not be multiplied beyond what is necessary and therefore what can be done with the fewest assumptions should not be done with more.

Another response to the jump from the third premise of the causal argument to its conclusion might be. Proponents of Emergentism seek to dispose of such arguments by presenting mental phenomena as brute emergent phenomena. They hold that there is ‘no explanation of why anything conscious should emerge from neural-biological processes,’ let along to suggest why they are two concepts that describe the same thing. Followers would hold that when biological mechanism and components reach a certain level of complexity a new type of phenomena emerges and that these emergent phenomena ‘are not explainable in terms of lower level physical-biological phenomena.’ Hence the mental is the mental is something that emerges from the physical and we should expect no further explanation of this brute fact. Emergentism, however, is fairly easy to critique on the basis of its implied casual closure and so I will move on swiftly from this objection.

In terms of the concluding premise of the causal argument it is also argued that the jump to say that all mental events are identical with physical events poses the objection that even if sensations are identical to certain brain processes there are still ‘introspected non-physical’ properties of sensations that cannot be identical. This objection prompts Smart’s concept of topic neutral events. But I shall no tbe discussing this any further as its implications reflect more on the idenity theory as a whole rather than the causal argument specifically.

Here I feel it necessary to note that although plausible, the causal argument still seems more like “a research programme in conceptual analysis rather than a developed theory,’ and is as Papineau suggests, relatively abstract. For the causal argument to be a proof of any kind it requires empirical information. It is not enough merely to state that mental states are identical with ‘some part of the full physical histories behind their effects,’ we must know more detailed correlations; this is where the empirical evidence can complement the theory but standing alone the theory cannot tell us which mental states should be paired up with which physical states, and therefore can only theorise about rather than firmly establish claims; But importantly can reasonably show that the two are not merely correlated in some indefinable way that requires the ‘natural piety’ of emergentism for example but are in fact show the two to be different concepts with the same referent.

I have left the most prominent objection to the causal argument till last as it is demonstrably is, and has been regarded as a successful objection that the causal argument cannot refute. The Causal argument’s fourth premise holds that mental properties are identical to strictly physical ones. This encounters the problem that it is easy to prove that creatures who can share the same conscious states, do not always share any similarity, let alone identity in their neural or simply physical properties. For example, empirical evidence can prove that certain animals, vastly different to humans in their composition, can experience pain too. So if pain = brain state 34= C fibres firing (Papineau), a monkey can experience pain but has a different neural and physical composition to humans and does not have C fibres, for example. This objection to the causal argument is known as Multiple Realization and roughly holds that creatures which are incapable of the exact same brain states due to their physical composition, can still share mental states so the mental state is multiply realized. So in my above example, we can reject the firing of C fibres as being identical to pain sensation, and as Putnam suggests move towards the idea of identifying it with its functional roles.

By taking this convincing line of argument we are, however, forced to abandon at least some if not all of the causal arguments claims, but it has been argued that it is possibly to reconstruct the causal argument in a way that reaches the functionalist conclusion. As Papineau notes, it could be possible by first adjusting the first premise of the causal argument to imply a much weaker sense of causal roles, giving the possibility of causing physical effects or potentially having what Papineau calls ‘realizers’ that directly cause them. This allows for a much less strict identification with physical states and gives a means of ‘identifying them with second order states which are physically realized.’ Hence we may conclude that if mental states are not strictly identical with the corresponding physical states, they must at least be identical with functional ‘role’ properties that are physically realized for there to be causal fluidity between the two. Without this adjustment the causal argument for the identity theory still stands as plausible and appealing theory that marks progress in theories of mental causation. Though it has difficulty withstanding the problem of multiple realisation it is still of some value, particularly when accompanied with empirical evidence rather than as an abstract, and can be used comfortably to support the identity theory and physicalism and shed some light in conceptual analysis in this field.

References

• Armstrong, D. M. “the Casual Theory of the Mind” Philosophy of Mind: Classical and Contemporary Readings [New York, Oxford University Press, 2002]

• Bennett, Karen. “Why the Causal Exclusion Problem Seems Intractable, and How, Just Maybe, To Tract it” ,  (p 471-497)

• Fodor, Jerry. “Making Mind Matter More,” A Theory of Content and Other Essays [Cambridge, MIT Press, 1990]

• Jaegwon, Kim. Philosophy of the Mind (2nd ed) [USA, Westview Press, 2006]

• Lewis, David. “Pyschophysical and Theoretical Identifications” Philosophy of Mind: Classical and Contemporary Readings, David J. Chalmers [New York, Oxford University Press, 2002]

• Papineau, David. Thinking About Consciousness [Oxford, Clarendon Press, 2002]

• Papineau, David “Mind the Gap”

http://www.kcl.ac.uk/ip/davidpapineau/Staff/Papineau/OnlinePapers/MindtheGap.html

• Place, U. T. “Identity Theories”

• Putnam, Hilary. “The Nature of Mental States” Philosophy of Mind: Classical and Contemporary Readings, David J. Chalmers [New York, Oxford University Press, 2002]

• Smart, J. J. C “The Identity Theory of the Mind” (revised May 18th 2007)

• Smart, J. J. C. “Sensations and Brain Processes” Philosophy of Mind: Classical and Contemporary Readings, David J. Chalmers New York, Oxford University Press, 2002]

• Yablo, Stephen. “Mental Causation” Philosophy of Mind: Classical and Contemporary Readings, David J. Chalmers [New York, Oxford University Press, 2002]

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