Jaegwon Kim

(1934 - 2019)

Thirty-two years ago W. V. Quine proposed a definition of 'logical truth' that has been widely repeated and reprinted. Quine himself seems to have recognized that this definition is wrong in detail; in section 1 we eliminate this fault. What has perhaps been less widely observed is that, in abandoning the model-theoretic account of logical truth in favor of a "substitutional" account, Quine's definition swells the ranks of the logical truths and makes the classification of a sentence as a logical truth dependent both on the interpretation of its extralogical words and on the extralogical vocabulary available in the language.

Jackson says that the form of physicalism that I recommend, with certain emendations he believes are necessary, turns out to be none other than the “Australian” type-type identity theory of J.J.C. Smart and others. About this, too, I have no serious disagreement, although Jackson’s claim appears to depend, at least in part, on a certain chosen reading of the texts involved. In fact, one point of similarity may be worth noting. As I take it, one special feature of the “Australian” type identity theory is the claim that mental-physical identities are contingent, not necessary. Suppose M has a single physical realizer, P. On my account, the statement that M = P is not metaphysically or logically necessary. It is contingent since the statement that P realizes M is contingent. This is so because for P to realize M is for it to fulfill the causal specification that defines M, and what causal relations P actually enters into is a question that depends on the laws prevailing in a given world. Thus, P may be a realizer of M in this world but perhaps not in another in which different laws hold; in some worlds M may have no realizers at all. None of this is in violation of the idea that identities are necessary. For, according to me, if M has realizers, M is a functional property defined by a causal specification. This means that “M” is not a rigid designator, though it is, as we might call it, “nomologically rigid” or “semi-rigid”.

For the physicalist, the mind-body problem is the problem of finding a place for the mind in a world that is fundamentally physical. What does “fundamentally physical” mean? I think any physicalist will accept at least the following two claims. First, the world contains nothing but bits of matter and aggregates of bits of matter. There are no Cartesian souls, or Hegelian spirits, or neo-vitalist entelechies—as the emergentist C. Lloyd Morgan put it, no “alien influx” into the natural order. This ontological thesis is sometimes called “ontological physicalism”. Second, we have the supervenience thesis: physical facts determine all the facts, and the physical properties of a thing determine all its properties. At this point, then, the world looks like this: all the things that exist are physical things—either basic bits of matter or wholly made up of bits of matter. These physical things have properties. What properties? First, there are basic physical properties, like mass, size, shape, electric charge, and so on—properties and magnitudes in terms of which laws of physics are formulated. But some properties of complex physical systems, like biological organisms, seem prima facie nonphysical—at least, they are not among the properties investigated in physics or the physical sciences. Prominent among them are mental properties—beliefs, desires, sensations, emotions, and the rest. The supervenience thesis says that such properties are fixed by the physical properties of the systems that have them; once the physical properties of a system are fixed, that fixes all of its properties. And yet property dualists, or nonreductive physicalists, maintain that although certain non-physical properties are determined by physical properties, they are irreducible to, and remain distinct from, physical properties. Although thoughts and pains are determined by the biology, and ultimately physicochemistry, of an organism, they are not biological/physical properties themselves, and there exists a special autonomous science of psychology, or cognitive science, that is responsible for investigating them.

Une des doctrines centrales de l’émergentisme est la thèse selon laquelle certaines propriétés d’un tout sont émergentes, en ce sens qu’elles sont irréductibles aux propriétés de base dont elles émergent — c’est-à-dire qu’elles ne peuvent ni être prédites, ni être expliquées à partir de leurs conditions sousjacentes. Pour comprendre et évaluer cette thèse correctement, il est essentiel que nous disposions d’un concept adéquat de réduction. Nous examinons d’abord le modèle classique de la réduction interthéorique de Nagel, et nous soutenons qu’il ne nous fournit pas une base adéquate pour comprendre la thèse émergentiste. Nous proposons ensuite un autre modèle de réduction, celui de la « réduction fonctionnelle », et nous montrons qu’il constitue une base adéquate permettant d’évaluer la thèse émergentiste. Nous concluons avec une brève discussion de la question de savoir si les propriétés phénoménales d’expériences conscientes, ou qualia , sont émergentes.A central doctrine of emergentism is the thesis that some properties of wholes are emergent in the sense that they are irreducible to the “basal” properties from which they emerge — that is, they are neither predictable nor explainable in terms of their underlying conditions. To understand and properly evaluate this claim, it is essential that we have at hand an appropriate concept of reduction. This paper first examines the classic Nagel model of inter- theoretic reduction and finds it wanting as a basis for understanding the emergentist claim. Another model of reduction, “functional reduction”, is proposed, and it is argued that this model does provide an appropriate basis for evaluating the claim that certain properties of wholes are emergent. The paper closes with a brief discussion of the question whether qualia , or the phenomenal properties of conscious experience, are emergent

This paper offers a critique of the view that causation can be analyzed in terms of explanation. In particular, the following points are argued: a genuine explanatory analysis of causation must make use of a fully epistemological-psychological notion of explanation; it is unlikely that the relatively clear-cut structure of the causal relation can be captured by the relatively unstructured relation of explanation; the explanatory relation does not always parallel the direction of causation; certain difficulties arise for any attempt to construct a nonrelativistic relation of causation from the essentially relativistic relation of explanation; and to analyze causation as explanation is to embrace a form of “causal idealism”, the view that causal connections are not among the objective features of the world. The paper closes with a brief discussion of the contrast between the two fundamentally opposed viewpoints about causality, namely causal idealism and causal realism.