Anomalous Monism

The Theory

Central to the AM are (a) the claim that, in addition to other particulars like objects, there also exist individual events (an event, in this sense, only occurs once, although the same type of event may recur), (b) a view of causation as a relation holding between individual events no matter how they are described (hence, an extensional relation) but always involving strict laws covering cause and effect, and (c) the distinction between events and descriptions true of them. In Davidson's view, events are mental insofar as they have true descriptions essentially couched in predicates expressing propositional attitudes (like “believes,” “wants,” etc.); events are physical insofar as they have true descriptions using only physical terms essentially.

AM aims to reconcile three principles seemingly in tension: the principle of causal interaction, the principle of the nomological character of causality, and the principle of the anomalousness of the mental.

• 1.
  Principle of causal interaction: Some mental events interact causally with some physical events.
• 2.
  Nomological character of causality: Events related as cause and effect fall under strict (exceptionless) laws.
• 3.
  Anomalousness of the mental: There are no strict laws on the basis of which mental events may be predicted or explained.

According to Davidson, these are all true. The key to reconciling the anomalousness of the mental with the nomological character of causality and the principle of causal interaction between the mental and the physical, which together suggest its falsity, is to allow that mental events interacting causally fall under strict laws but that these laws can only be stated using nonmental descriptions. On Davidson's view, only physical descriptions are apt for expressing strict laws. Because, by the principle of causal interaction and the nomological character of causality, mental events do fall under strict laws, they must have physical descriptions. Hence, they are physical.

In AM, the existence of events must be clearly separated from how they are described for purposes of particular explanatory interests. In describing a certain event as an action, and explaining it by a belief and a desire of the agent, together constituting her reason for the action, we employ a vocabulary suited to displaying the action as rational (from the agent's point of view). But explanatory force also requires that the reason cause the effect, and, in felicitous cases, this is true. We thereby pick out events related as cause and effect; these also have (some, complicated) physical descriptions, but mental events are identifiable as instances of salient general categories only by means of descriptions unsuited to incorporation in strict laws.

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