Davidson makes a distinction between mental and physical descriptive generalizations; physical generalizations are strict, for example, the principle of transitivity: if x is longer than y and y is longer than z then x must be longer than z, if there was a situation where this was not the case then it would be dismissed and a new law created. However, Davidson would say that mental generalizations are normative, they are how things should be not how they are. He maintains that the reason why they are normative is that mental states are governed by the constitutive ideal of rationality. By this, Davidson means that, in general, we would act within our interests but, unlike the principle of transitivity, if we were to act against what we should do does not make the generalization that we act rationally and in our interests false, it merely means that The individual was not acting as a rational agent. For example, the addict may well know his addiction serves him no good and only causes harm yet he will continue acting against his interest.
Through an exploration of DavidsonsΒ principle of causal interaction, some mental events are caused by physical events and vice versa, for example, raising a hand in a lesson has been caused by a m
ental event of me wanting to raise a hand, however, the mental event that caused me to raise my hand could have been casually caused by the teacher asking a question. He also adds what he calls The Principle of the Nomological character of causation (PNCC), which adds that all singular causal interactions must be covered by strict laws. Davidson doesnΒt immediately provide a defense of these principles however we can find his justifications deeper into his writings. These principles would lead most people to think that Davidson is going to define some psychological laws; for example, if a mental event labeled m is caused by a physical event p, then given the Principle of the Nomological Character of causation, it would seem as if there must be a strict law of p -> m; whenever p must then m, Davidsons puts this where there is causality, there must be a law (Davidson,99). Davidson however believes that properties are incapable of being held to universal laws, this is the anomalism principle, part of anomalous monism. the anomalism principle states There are no strict laws on the basis of which mental events can predict, explain, or be predicted or explained by other events (Anomalous Monism, Stanford Encyclopedia of Philosophy, 2020),