Online research in philosophy

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.

One view of the nature of properties has been crystallized in recent debate by an identity thesis proposed by Shoemaker. The general idea is that there is for behaviour. Well-known criticisms of this approach, however, remain unanswered, and the details of its connections to laws nothing more to being a particular causal property than conferring certain dispositions of nature and the precise ontology of causal properties stand in need of development. This paper examines and defends a dispositional essentialist account of causal properties, combining a Shoemaker-type identity thesis with a Dretske, Tooley, and Armstrong-type view that laws are relations between properties, and a realism about dispositions. The property identity thesis is defended against standard epistemological and metaphysical objections. The metaphysics of causal properties is then clarified by a consideration of the laws relating them, vacuous laws, and ceteris paribus law statements.

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 is an attempt to understand the content of, and motivation for, a popular form of physicalism, which I call ‘non-reductive physicalism’. Non-reductive physicalism claims although the mind is physical (in some sense), mental properties are nonetheless not identical to (or reducible to) physical properties. This suggests that mental properties are, in earlier terminology, ‘emergent properties’ of physical entities. Yet many non-reductive physicalists have denied this. In what follows, I examine their denial, and I argue that on a plausible understanding of what ‘emergent’ means, the denial is indefensible: non-reductive physicalism is committed to mental properties being emergent properties. It follows that the problems for emergentism—especially the problems of mental causation—are also problems for non-reductive physicalism, and they are problems for the same reason.

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.

Emergence has traditionally been described as satisfying specific properties, notably nonreducibility of the emergent object or properties to their substrate, novelty, and unpredictability from the properties of the substrate. Sometimes more mysterious properties such as independence from the substrate, separate substances and teleological properties are invoked. I will argue that the latter are both unnecessary and unwarranted. The descriptive properties can be analyzed in more detail in logical terms, but the logical conditions alone do not tell us how to identify the conditions through interactions with the world. In order to do that we need dynamical properties – properties that do something. This paper, then, will be directed at identifying the dynamical conditions necessary and sufficient for emergence. Emergent properties and objects all result or are maintained by dissipative and radically nonholonomic processes. Emergent properties are relatively common in physics, but have been ignored because of the predominant use of Hamiltonian methods assuming energy conservation. Emergent objects are all dissipative systems, which have been recognized as special only in the past fifty years or so. Of interest are autonomous systems, including living and thinking systems. They show functionality and are self governed.

Emergent properties are intended to be genuine, natural higher level causally efficacious properties irreducible to physical ones. At the same time they are somehow dependent on or 'emergent from' complexes of physical properties, so that the doctrine of emergent properties is not supposed to be returned to dualism. The doctrine faces two challenges: (i) to explain precisely how it is that such properties emerge - what is emergence; (ii) to explain how they sidestep the exclusion problem - how it is that there is room for these properties to be causally efficacious, given the causal completeness of the physical. In this paper I explain how functional properties can meet both challenges.

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.

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.

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.