Online research in philosophy

This paper explicates two notions of emergencewhich are based on two ways of distinguishinglevels of properties for dynamical systems.Once the levels are defined, the strategies ofcharacterizing the relation of higher level to lower levelproperties as diachronic and synchronic emergenceare the same. In each case, the higher level properties aresaid to be emergent if they are novel or irreducible with respect to the lower level properties. Novelty andirreducibility are given precise meanings in terms of the effectsthat the change of a bifurcation or perturbation parameterin the system has. (The same strategy can be applied to otherways of separating levels of properties, like themicro/macro distinction.)The notions of emergence developed here are notions of emergencein a weak sense: the higher level emergent properties wecapture are always structural properties (or are realized insuch properties), that is, they are defined in terms of the lowerlevel properties and their relations. Diachronic and synchronicemergent properties are distinctions within thecategory of structural properties.

In the first section of this paper, I articulate Jaegwon Kim's argument against emergent down ward causation. In the second section, I canvas four responses to Kim's argument and argue that each fails. In the third section, I show that emergent downward causation does not, contra Kim, entail overdetermination. I argue that supervenience of emergent upon base properties is not sufficient for nomological causal relationsbetween emergent and base properties. What sustains Kim's argument is rather the claim that emergent properties realized by base properties can have no causal powers distinct from those base properties. I argue that this is false.

The paper argues in favour of (1) a causal-functional theory of all properties including the physical ones and (2) a conception of properties as tropes or modes in the sense of particular ways that objects are. It shows how these premises open up a version of functionalism according to which the properties on which the special sciences focus are identical with configurations of physical properties and thereby causally efficacious without there being any threat of eliminativism.

Emergent properties (EPs) are not causally reducible to the properties of a complex system’s elements. If a system’s properties cannot be reduced to those of any of its components, then that system is effectively a singular entity (SE). EPs are thus not properties of known complexes, but of SEs. A precise description of the parameters necessary to observe a physical system as an SE is thus necessary to establish under what conditions properties are understood as emergent. That description is provided in terms of the temporal dynamics of systems and their internal/external interactions.

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.

Is there a problem of causal exclusion between micro- and macro-level physical properties? I argue (following Kim) that the sorts of properties thatin 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 understandinstances of macro-structural properties to be parts ofmicro-structural property instances. The parthood relation between both kinds of property instances can bemapped onto the way physical theory deals with the relation of their descriptionsin the framework of perturbation theory. The application of this framework to theproblem of emergent properties is discussed.

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.

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 a recent paper, Bird (in: Groff (ed.) Revitalizing causality: Realism about causality in philosophy and social science, 2007 ) has argued that some higher-order properties—which he calls “evolved emergent properties”—can be considered causally efficacious in spite of exclusion arguments. I have previously argued in favour of a similar position. The basic argument is that selection processes do not take physical categorical properties into account. Rather, selection mechanisms are only tuned to what such properties can do, i.e., to their causal powers. This picture seems ultimately untenable in the light of further exclusion problems; but at the same time, it meets our explanatory demands. My purpose is therefore to show that there is a real antinomy with regard to evolved emergent properties. I develop a physicalist exclusion argument and then I go on to consider an argument that seems to establish that evolved emergent properties are causally efficacious, and propose a compatibilist solution. Finally, I very briefly consider what the proposed model may imply for the issue of mental causation.

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.