Online research in philosophy

The hypothesis of the mental state-causation of behavior (the MSC hypothesis) asserts that the behaviors we classify as actions are caused by certain mental states. A principal reason often given for trying to secure the truth of the MSC hypothesis is that doing so is allegedly required to vindicate our belief in our own agency. I argue that the project of vindicating agency needs to be seriously reconceived, as does the relation between this project and the MSC hypothesis. Vindication requires addressing what I call the agent-exclusion problem: the prima facie incompatibility between the intentional content of agentive experience and certain metaphysical hypotheses often espoused in philosophy.

Stephen Yablo has recently argued for a novel solution to the mental causation problem: the mental is related to the physical as determinables are related to determinates; determinables are not causal rivals with their determinates; so the mental and the physical are not causal rivals. Despite its attractions the suggestion seems hard to accept. In this paper I develop the idea that mental properties and physical properties are not causal rivals. Start with property dualism, supervenience, multiple realizability, and the claim that no more than one supervenience base for a mental property can be had by a single instance of the mental property. Then a probabilistic account of causation will be unable to certify either mental properties or physical properties as causal factors for effect types. I suggest that this shows that we should not count mental properties as causal rivals with physical properties.

This paper argues that the non-reductive monist need not be concerned about the ‘problem’ of mental causation; one can accept both the irreducibility of mental properties to physical properties and the causal closure of the physical. More precisely, it is argued that instances of mental properties can be causally efficacious, and that there is no special barrier to seeing mental properties whose instances are causally efficacious as being causally relevant to the effects they help to bring about. It is then shown that the causal relevance of mental properties is consistent with there being no downward causation, so the dilemma of ‘epiphenomenalism or reduction’ can be avoided. Non-reductive monism lives on as a viable position in the philosophy of mind.

Recent discussions of mental causation have focused on three principles: (1) Mental properties are (sometimes) causally relevant to physical effects; (2) mental properties are not physical properties; (3) every physical event has in its causal history only physical events and physical properties. Since these principles seem to be inconsistent, solutions have focused on rejecting one or more of them. But I argue that, in spite of appearances, (1)–(3) are not inconsistent. The reason is that 'properties' is used in different senses in the principles. In (1) and (3), 'properties' should be read as 'tropes' (properties here are particulars), while in (2) 'properties' should read as 'types' (properties here are universals or classes). Although mental types are distinct from physical types, every mental trope is a physical trope. This allows mental properties to be causally relevant to physical effects without violating the closed character of the physical world.

The anti-reductionist who wants to preserve the causal efficacy of mental phenomena faces several problems in regard to mental causation, i.e. mental events which cause other events, arising from her desire to accept the ontological primacy of the physical and at the same time save the special character of the mental. Psychology tries to persuade us of the former, appealing thereby to the results of experiments carried out in neurology; the latter is, however, deeply rooted in our everyday actions and beliefs and despite the constant opposition of science still very much alive. Difficulties, however, arise from a combination of two claims that are widely accepted in philosophy of mind, namely, physical monism and mental realism, the acceptance of which leads us to the greatest problem of mental causation: the problem of causal exclusion. Since physical causes alone are always sufficient for physical effects mental properties are excluded from causal explanations of our behaviour, which makes them “epiphenomenal”. The article introduces Van Gulick’s solution to the exclusion problem which tries to prove that physical properties, in contrast to mental properties, do not have as much of a privileged status with respect to event causation as usually ascribed. Therefore, it makes no sense to say that physical properties are causally relevant whereas mental properties are not. This is followed by my objection to his argument for levelling mental and physical properties with respect to causation of events. I try to show that Van Gulick’s argument rests on a premise that no serious physicalist can accept.

In this paper I argue that the problem of mental causation can be solved by distinguishing between classificatory mental properties, like being a pain, and instances of those properties.Antireductive physicalism allows only that the former be irreducibly mental. Consequently, properties like being a pain cannot have causal commerce with the physical without violating causal closure. But instances of painfulness, according to the token identity thesis, are identical with various physical tokens and can therefore have causal efficacy in the physical world. Since we expect particular mental phenomena, not types or classes of mental phenomena to be involved in causal interactions, it is argued that antireductive physicalism can explain satisfactorily mental causation, despite the protests of Kim, Sosa, Honderich, and others. Being a mental state of a certain sort may have no causal efficacy, but the intentional and phenomenal properties of such states should, if my argument is correct.

Sydney Shoemaker has attempted to save mental causation by a new account of realization. As Brian McLaughlin argues convincingly, the account has to face two major problems. First, realization does not guarantee entailment. So even if mental properties are realized by physical properties, they need not be entailed by them. This is the first, rather general metaphysical problem. A second problem, which relates more directly to mental causation is that Shoemaker must appeal to some kind of proportionality as a constraint on causation in order to avoid redundant mental causation. I argue that, in addition, a “piling problem” arises, since causal powers seem to be bestowed twice. Then, I try to sketch an alternative view of the relation between causal powers and properties—a reductionist view—which fares better on some accounts. But it may have to face another and, perhaps, serious problem, the “problem of the natural unity of properties”. Finally, I will pose a question about the relation between causal powers and causation.

It is quite obvious why the antireductionist picture of mental causation that rests on supervenience is an attractive theory. On the one hand, it secures uniqueness of the mental; on the other hand, it tries to place the mental in our world in a way that is compatible with the physicalist view. However, Kim reminds us that anti-reductionists face the following dilemma: either mental properties have causal powers or they do not. If they have them, we risk a violation of the causal closure of the physical domain; if they do not have them, we embrace epiphenomenalism, which denies any sort of causal powers to the mental. So, either we violate the causal closure of physics, or we end up with epiphenomenalism. The first two sections of the article describe the problem of causal exclusion and Kim’s causal dilemma. The last two introduce Horgan’s antireductionist answer and my objection to that answer.

We have a familiar idea of levels of description or levels of theory in science: microphysics, atomic physics, chemistry, biology, psychology, and the various social sciences. It is clear that philosophers - such as Terry Horgan - who want to be nonreductive materialists with regard to the mental must hold that this is not mere description; there must be genuine higher-level causes, and hence, genuine higher-level properties, in particular mental properties and causes. But there appears to be a deep problem concerning mental causes. The (micro-) physical world is causally closed. Mental states are - or depend on or are realized by - physical states. It seems, then, that the physical state on which a mental state depends will be responsible for any alleged effects of the mental state. There will be no room for mental causation. And if properties exist insofar at they have a causal role, there will be no room for mental properties either. Many philosophers - Horgan included - have seen this problem of the "causalexclusion" ofthe mental as a specialcase of a general problem:the exclusion of higher-level causes by the causal closure of microphysics. Suppose one higher-level state, H1 leads to another higher-level state, H2. H1 is realized by some base level state, B1, which leads to a base-level state, B2, which in turn realizes H2. All of the casual work, so to speak, takes place at the base level. There is no room for any genuine causal connection between H1, as such, and H2, as such. I argue that there is no problem about higher-order causation in general. There are genuine, unsurprising higher-level causes and properties. A ball roles, for example, or breaks a window. If there is a problem of exclusion regarding putative mental causes, it is not an instance of a general exclusion problem, but is sui generis, and mental causation remains mysterious.

Terry Horgan University of Memphis In this paper I address the problem of causal exclusion, specifically as it arises for mental properties (although the scope of the discussion is more general, being applicable to other kinds of putatively causal properties that are not identical to narrowly physical causal properties, i.e., causal properties posited by physics). I summarize my own current position on the matter, and I offer a defense of this position. I draw upon and synthesize relevant discussions in various <blockquote> [1] </blockquote> other papers of mine (some collaborative) that bear on this topic.