Exclusion argument

My next chapter focuses issues of closure, drainage, and seepage. I discuss Ned Block s criticism that Kim s exclusion argument leads to the problems of seepage (i.e., causation at any irreducible supervenient level will always be pre-empted by causation at a subvenient level below it) and drainage (i.e., if matter is infinitely divisible, and there is no lowest level, then causation will drain away endlessly and we will be left with no... 

This type of objection to nonreductive materialism is central to the work of Jaegwon Kim. Kim discusses this objection extensively in the various versions of his exclusion argument or supervenience argument. He holds that the only way to give mental properties a causal role is to functionally reduce them to physical properties, since physical causation will always rule out causation in virtue of irreducible mental... 

This line of objection to nonreductive materialism again is the type of objection that Kim makes in his discussion of the exclusion argument. In chapters 3 and 4 to come, I discuss this objection in further detail and argue that we have no good reason to think that all or even most scientific properties are reducible to the properties of physics. Thus, if causation at the level of physics does not rule out causation in virtue of irreducible higher-level scientific properties, then we have no good reason to think that it should rule... 

This chapter has asked whether the anomalism of mental properties rules out causation in virtue of these mental properties. Although this chapter has focused upon Davidson s view in particular, this problem is relevant to all nonreductive materialist views, since all nonreductive materialist views hold that mental properties are anomalous. If all cases of causation are backed by strict causal laws, then it might seem that mental properties can never be causal, since anomalous mental properties will never be part of these strict laws. I have argued however that even if all causation is backed by strict laws, mental properties can still be causal, since strict laws do not rule out causation in virtue of higher-level properties that are not part of those laws. I have raised two possible objections to this last claim, which are discussed in great detail in the next three chapters. Let us now turn to the first of these objections - Jaegwon Kim s exclusion argument. 

Kim discusses the exclusion principle in various works. See, e.g., Kim 1993a, 1993b, 1996 ch.6, 1998, 2005. Although the main points of the argument are the same in all of these works, the versions of Kim s exclusion argument on which I will primarily focus are the ones set forth in Kim 1998 and 2005, since these are his most recent comprehensive discussions of the exclusion argument. 

Two extremely similar versions of the exclusion argument are presented in Kim 1998 41-5 and Kim 2005 39-43. I will here, for the most part, present the argument as put forth in Kim 2005, as this version is slightly clearer. However, I will sometimes quote parts of the argument put forth in Kim 1998 (instead of... 

If these are the only kinds of cases that can be called cases of causal overdetermination, then Kim is right that it is absurd to think that all cases of mental causation are cases of overdetermination. If we use the term overdetermination as Kim seems to here, then we should reject the idea that P is causally overdetermined by M and P. Surely M and P are not completely independent and individually sufficient causes for P. Rather, M and P are related by supervenience (and possibly also by realization and event identity as well). It is not as if M could have caused P even if P had not occurred. If P had not occurred, M would not have occurred either - M depends on P for its existence. Thus, it seems plausible to accept premise (7) in Kim s exclusion argument - i.e. that P is not causally overdetermined by M and P. 

Thus, if we use this version of the exclusion principle in Kim s exclusion argument, we will not get Kim s desired conclusion. This version of the exclusion principle says that two distinct events cannot both cause P. But as long as we hold the event identity of M and P, then as event, M and P are token identical. M and P are only distinct as properties. Since this version of the exclusion principle only requires us to rule out distinct events as both being causal, but not distinct properties, this version will not force us to rule out either M or P as a cause of P. Thus, this version of the exclusion principle, while independently plausible, will not get Kim to his desired conclusion (8) -i.e. that mental property M gets excluded by physical property P as the cause of P. ... 

The above considerations show that as long as we hold M and P to be token identical events, Kim s plausible version of the exclusion principle will not rule out mental events as causal. This is good reason for the nonreductive materialist to hold a Davidsonian view of event identity. It seems that a mere supervenience or realization relation between M and P is not quite enough. In addition to supervenience and realization, it seems that we also need the token event identity of M and P, in order to avoid M getting ruled out as causal by the plausible exclusion principle. Thus, fijom this point forward, I will assume that any viable nonreductivist position requires that M and P are token identical events. I will, from now on, assume a Davidsonian event identity. 3.3 Kim s second formulation of the exclusion principle Kim s second formulation of the exclusion principle, which actually appears in the exclusion argument is as follows ... 

Now the question we need to ask is whether the revised exclusion principle seems plausible. Kim s first version of the exclusion principle about events seems independently plausible, but as we have seen does not make his exclusion argument work. If we want the argument to work, we have to take the principle as referring to... 

So it seems that in this scenario, where we have closure at L - 1 with respect to L, the exclusion principle and seepage will both apply. The causal powers of properties at L will always be preemped by properties at L - 1. Causation need not seep down to a lowest closed level for the exclusion argument to work. Instead, it seems that if the exclusion principle applies to all irreducible supervenient levels, then whenever there is closure of a subvenient level with respect to its supervenient level, causation will seep... 

First, it is important to note that Kim s view is utterly committed to the causal closure of the physical domain. Kim has stated many times that he believes in the causal closure of the physical domain. Yet it seems that in addition to merely asserting this belief, Kim s entire theory requires that there be some lowest closed level (or closed union of levels). First of all, Kim seems to think that a bottom closed level is required in order to make the exclusion argument even work (if it does work). I have raised my... 

The notions of the causal closiue of the physical domain and the causal closure of specific levels of organization are central to both Kim s exclusion argument and his response to generalization worries. The idea of causal closure of the physical domain is... 

The two big issues that are central in deciding who wins this debate are exclusion and context dependence. Anyone who buys the exclusion argument will have to reject nonreductive materialism. Anyone who believes that mental properties and other higher-level properties are context dependent will have to reject functional reduction. 

Since these are the crucial issues in the debate, my argument against ftmctional reduction and for nonreductive materialism is two-fold. First I argue against the exclusion argument. If I am successful, then what I have done is left nonreductive materialism as a viable option. The purpose of the exclusion argument is to show that nonreductive materialism cannot account for mental causation because it cannot make irreducible mental properties causal. If the exclusion argument worked, then we would... 

This however, would not show that functional reduction is the right theory. As long as 1 can successfijlly show that the exclusion argument fails, then both nonreductive... 

Let me begin with a close reading of Kim s most recent formulation of the exclusion argument, with an eye toward seeing just how Kim thinks he has defused the generalization bomb. Chapter 2 of Mind in a Physical World, The Many Problems of Mental Causation, introduces the exclusion problem with the admonition that it strikes at the very heart of physicalism (p. 30). It arises, he says, for anyone who accepts two modest metaphysical commitments the thesis that the mental supervenes on the physical, and the thesis that the mental is realized in the physical. Denial of either of these theses is tantamount, in Kim s opinion, to the rejection of physicalism. 

So, here s the exclusion argument itself Suppose that some M-instantiation causes an TVf-instantiation. By supervenience, we know that the -instantiation has a physical supervenience base, But P -instantiation is nomologicaUy sufficient for AP-instantiation. It therefore appears that Af and P each have a claim to being responsible for the instantiation of Af on this occasion, and the two claims appear to be in tension with each other. The only plausible way to resolve this tension is to conclude that the Af-instantiation causes the AP-instantiation by causing a P-instantiation. But, again by supervenience, Afhas a supervenience base, P. By the causal closure of the physical, the P-instantiation must have a complete physical cause — presumably, the P-instantiation. But now P and M are in direct competition for being the cause of the P-instantiation. ... 

With the distinction between economical and loose reduction in mind, let s turn to Kim s treatment of multiply realizable properties in chapter 4 of MIPW. We may suppose, with Kim, that the exclusion argument provides a strong reason to seek a reduction of mental properties to physical properties we may also note — though Kim does not — that the reduction will afford a solution only if it is an economical one. The ostensible problem with multiply realizable mental properties is that their multiplicity of realizers apparently precludes strong type reductions pain cannot be identified with the firing of C fibers if some creatures realize... 

Microbased properties are supposed to be immune from the exclusion argument. Why Fundamentally, because they represent novel causal powers, novel relative to the causal powers of their constituent properties and relations. Recall the conclusion of the passage quoted earlier ... 

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