Copyright © 1999 Massachusetts Institute of Technology
Anomalous monism is the thesis that mental entities (objects and events) are identical with physical entities, but under their mental descriptions mental entities are neither definitionally nor nomologically reducible to the vocabulary of physics. If we think of views of the relation between the mental and the physical as distinguished, first, by whether or not mental entities are identical with physical entities, and, second, divided by whether or not there are strict psychophysical laws, we get a fourfold classification: (1) nomological monism, which says there are strict correlating laws, and that the correlated entities are identical (this is often called materialism); (2) nomological dualism (interactionism, parallelism, epiphenomenalism); (3) anomalous dualism, which holds there are no laws correlating the mental and the physical, and the substances are discrete (Cartesianism); and (4) anomalous monism, which allows only one class of entities, but denies the possibility of definitional and nomological reduction. It is claimed that anomalous monism is the answer to the MIND-BODY PROBLEM, and that it follows from certain premises, the main ones being:
Take an arbitrary mental event M. By (1), it is causally connected with some physical event P. By (2), there must be a strict law connecting M and P; but by (3), that law cannot be a psychophysical law. Because only physics aims to provide a closed system governed by strict laws, the law connecting M and P must be a physical law. But then M must have a physical description -- it must be a physical event. (The term "anomalous monism" and the argument were introduced in Davidson 1970.)
The three premises are not equally plausible. (1) is obvious. (2) has seemed true to many philosophers; HUME and KANT are examples, though their reasons for holding it were very different (Davidson 1995). It has been questioned by others (Anscombe 1971; Cartwright 1983). A defense of (2) would begin by observing that physics is defined by the aim of discovering or devising a vocabulary (which among other things determines what counts as an event) which allows the formulation of a closed system of laws. The chief argument for the nomological and definitional irreducibility of mental concepts to physical is that mental concepts, insofar as they involve the propositional attitudes, are normative, while the concepts of a developed physics are not. This is because propositions are logically related to one another, which places a normative constraint on the correct attribution of attitudes: since an attitude is in part identified by its logical relations, the pattern of attitudes in an individual must exhibit a large degree of coherence. This does not mean that people may not be irrational, but the possibility of irrationality depends on a background of rationality (Davidson 1991).
(3) rules out two forms of REDUCTIONISM: reduction of the mental to the physical by explicit definition of mental predicates in physical terms (some forms of behaviorism suggest such a program), and reduction by way of strict bridging laws -- laws that connect mental with physical properties. (1) - (3) do, however, entail ontological reduction, because they imply that mental entities do not add to the physical furniture of the world. The result is ontological monism coupled with conceptual dualism. (Compare Spinoza's metaphysics.) Anomalous monism is consistent with the thesis that psychological properties or predicates are supervenient on physical properties or predicates, in this sense of SUPERVENIENCE: a property M is supervenient on a set of properties P if and only if M distinguishes no entities not distinguishable by the properties in P (there are other definitions of supervenience).
A widely accepted criticism of anomalous monism is that it makes MENTAL CAUSATION irrelevant because it is the physical properties of events that do the causing (Kim 1993). The short reply is that it is events, not properties, that are causes and effects (Davidson 1993). If events described in physical terms are effective, and they are identical with those same events described in psychological terms, then the latter must also be causally effective. The vocabularies of physics and of psychology are irreducibly different ways of describing and explaining events, but one does not rule out, or supercede, the other.
Anscombe, G. E. M. (1971). Causality and Determination. Cambridge: Cambridge University Press.
Cartwright, N. (1983). How the Laws of Physics Lie. Oxford: Oxford University Press.
Davidson, D. (1980). Mental events. In D. Davidson, Essays on Actions and Events. Oxford: Oxford University Press.
Davidson, D. (1991). Three varieties of knowledge. In A. Phillips Griffiths, Ed., A. J. Ayer: Memorial Essays. Royal Institute of Philosophy Supplement, vol. 30. Cambridge: Cambridge University Press.
Davidson, D. (1993). Thinking causes. In J. Heil and A. Mele, Eds., Mental Causation. Oxford: Oxford University Press.
Davidson, D. (1995). Laws and cause. Dialectica 49:263-279.
Kim, J. (1993). Can supervenience and "non-strict laws" save anomalous monism? In J. Heil and A. Mele, Eds., Mental Causation. Oxford: Oxford University Press.
Copyright © 1999 Massachusetts Institute of Technology