Online research in philosophy

There are important cases where properties not referred to by expressions from the languages of physics are enabled in certain times and circumstances to get causal control over some kinds of physical events. I will argue that in those cases we would have to transfer to those properties the causal sufficiency to bring about these events. This would offer a principle of causal inheritance in sharp contrast with the inheritance principle for the causal sufficiency of second order properties defended by Jaegwon Kim in his recent discussion of the causal exclusion problem concerning mental properties. The two principles would be very different. Their domains of application would be distinct. Kim's principle would transfer causal sufficiency to the more "concrete" physical properties able to realize mental properties understood as second order properties. Our principle would transfer causal sufficiency to the more "general" properties able to cause the relevant physical effects in the times and circumstances in question. That way, it would be possible to give a quite simple answer to the problem of causal exclusion posed by Kim in relation to mental properties. Our approach also would have very important consequences in relation to ordinary macrophysical causation.

Sydney Shoemaker has recently given an account of emergent properties according to which emergent properties are a special type of structural property and the determination relation holding between emergent properties and their base properties is one of “mere nomological supervenience.” According to Shoemaker, emergent properties are what he calls type-2 microstructural properties, whereas physical properties are type-1 microstructural properties. After highlighting the advantages of viewing emergent properties as a special class of microstructural properties, I show how according to his own causal theory of properties type-2 microstructural properties actually reduce to type-1 microstructural properties, and thus do not truly count as emergent. I then suggest an alternative view according to which emergent properties are actually a third type of microstructural property, one not considered by Shoemaker. I conclude with reflections why we might view the dependence relation between emergent properties and their physical base properties as a causal relation rather than one of mere supervenience.

In this paper I examine Jaegwon Kim’s view that emergent properties are irreducible to the base properties on which they supervene. Kim’s view assumes a model of ‘functional reduction’ which he claims to be substantially different from the traditional Nagelian model. I dispute this claim and argue that the two models are only superficially different, and that on either model, properly understood, it is possible to draw a distinction between a property’s being reductively identifiable with its base property and a property’s being reductively explainable in terms of it. I propose that we should take as the distinguishing feature of emergent properties that they be truly novel properties, i.e., ontologically distinct from the ‘base’ properties which they supervene on. This only requires that emergent properties cannot be reductively identified with their base properties, not that they cannot be reductively explained in terms of them. On this conception the set of emergent properties may well include mental properties as conceived by nonreductive physicalists.

The systems studied in the special sciences are often said to be causally autonomous, in the sense that their higher-level properties have causal powers that are independent of those of their more basic physical properties. This view was espoused by the British emergentists, who claimed that systems achieving a certain level of organizational complexity have distinctive causal powers that emerge from their constituent elements but do not derive from them.2 More recently, non-reductive physicalists have espoused a similar view about the causal autonomy of specialscience properties. They argue that since these properties can typically have multiple physical realizations, they are not identical to physical properties, and further they possess causal powers that differ from those of their physical realizers.3 Despite the orthodoxy of this view, it is hard to find a clear exposition of its meaning or a defence of it in terms of a well-motivated account of causation. In this paper, we aim to address this gap in the literature by clarifying what is implied by the doctrine of the causal autonomy of special-science properties and by defending the doctrine using a prominent theory of causation from the philosophy of science. The theory of causation we employ is a simplified version of an “interventionist” theory advanced by James Woodward (2003, forthcoming a, b), according to which a cause makes a counterfactual difference to its effects. In terms of this theory, it is possible to show that a special-science property can make a difference to some effect while the physical property that realizes it does not. Although other philosophers have also used counterfactual analyses of causation to argue for the causal autonomy of special-science properties,4 the theory of causation we employ is able to establish this with an unprecedented level of precision..

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.

Kim’s model of ‘functional reduction’ of properties is shown to fail in a class of cases from physics involving properties at different spatial levels. The diagnosis of this failure leads to a non-reductive account of the relation of micro and macro properties.

In this note, I will discuss one issue concerning the main argument of Mind in a Physical World (Kim, 1998), the Causal Exclusion Argument. The issue is whether it is a consequence of the Causal Exclusion Argument that all macro level causation (that is, causation above the level of fundamental physics) is an illusion, with all of the apparent causal powers of mental and other macro properties draining into the bottom level of physics. I will argue that such a consequence would give us reason to reject the Causal Exclusion Argument. But there is also a stronger challenge, the charge that, if there is no bottom level of physics, the Causal Exclusion Argument has the consequence that “causal powers would drain away into a bottomless pit and there wouldn’t be any causation anywhere.” (81--page numbers that are not attributed to other works are to Kim, 1998).

It is often argued that higher-level special-science properties cannot be causally efficacious since the lower-level physical properties on which they supervene are doing all the causal work. This claim is usually derived from an exclusion principle stating that if a higher-level property F supervenes on a physical property F* that is causally sufficient for a property G, then F cannot cause G. We employ an account of causation as difference-making to show that the truth or falsity of this principle is a contingent matter and derive necessary and sufficient conditions under which a version of it holds. We argue that one important instance of the principle, far from undermining non-reductive physicalism, actually supports the causal autonomy of certain higher-level properties.

Emergence requires that the ultimate physical micro-entities have micro-latent causal powers, which manifest themselves only when the entities are combined in ways that are emergence-engendering, in addition to the micro-manifest powers that account for their behavior in other circumstances. Subjects of emergent properties will have emergent micro-structural properties, specified partly in terms of these micro-latent powers, each of which will be determined by a micro-structural property specified only in terms of the micro-manifest powers of the constituents and the way they are related. If the determiner and the determined properties are distinct, this determination is the basis of the supervenience of emergent properties on non-emergent physical properties. If not, emergence does not involve such supervenience. Either way, there is no problem with diachronic downward causation.

Is there a problem of causal exclusion between micro- and macro-level physical properties? I argue (following Kim) that the sorts of properties that in fact are in competition are macro properties, viz., the property of a (macro-) system of 'having such-and-such macro properties' (call this a 'macro-structural property') and the property of the same system of 'being constituted by such-and-such a micro- structure' (call this a 'micro-structural property'). I show that there are cases where, for lack of reducibility, there is a prima facie intra-level causal competition between the two kinds of properties. The problem can be resolved without giving up on the causal efficacy of the macro-structural properties if we understand instances of macro-structural properties to be parts of micro-structural property instances. The parthood relation between both kinds of property instances can be mapped onto the way physical theory deals with the relation of their descriptions in the framework of perturbation theory. The application of this framework to the problem of emergent properties is discussed.