‘Only the type-identity theory can secure the causal efficacy of the mental’ Discuss
In my essay I will argue that type-identity is the only theory that can secure the causal efficacy of the mental. I will first present the Identity theory as a theory for mental causation. I will then look to object this theory with the Functionalist position and Cartesian Dualism. However, I hope to show in what follows, that the type-identity theory provides solutions to the problems that both of these theories face using the causal exclusion argument. Throughout this essay, I will prove that type-identity theory is the only theory that can secure the causal efficacy of the mental.
The Identity Theory hold the position that all mental state types are physical types and therefore are identical to physical state types. This is to say that both mental and physical state types are one and the same thing as they are regarded as numerically identical. The Identity Theory can henceforth be used as an argument for physicalism as mental and physical states are regarded as one. One can use Princess Elizabeth’s Challenge to Cartesian Dualism argument to argue for the Identity Theory as a form of physicalism. Her argument is that mental states can cause physical effects in the same way that they physical states can. Seeing as how the physical effects of mental causes are not overdetermined, it is reasonable to say that mental states are therefore identical to physical states (Elizabeth in Shapiro, (2007) p. 62). Referring back to the example of pain, an Identity Theorist would hold the position that the state of pain is identical to the physical state of firing of C-fibers within the brain (Polger, (2009), p.822-834). In this way, the mental state type is identical to a corresponding brain state type. As a form of physicalism the identity theory can be considered as an a posteriori thesis meaning that it can be empirically supported by science. It is widely-known that there is a link between the mind and the brain which is arguably physical. The physical and chemical effects of drugs such as ecstasy have been seen to lead to changes in mental states including hallucinations. The change happening within the brain state is also occurring in the mental as they are both the same, henceforth supporting the type-identity argument.
Functionalism is also a theory which could be considered for the causal efficacy of the mental. It is the principle makes any type of mental state be defined by its functional role, rather than its “internal constitution” (Levin, (2016)). It argues for a mental state’s causal profile to show how a state can have causal outputs and inputs. Pain, for example, has the causal profile of being caused by some injury, it then causes behavioral changes such as crying or anxiety and finally leads someone to have the desire to no longer be within that state (Levin, (2016)). This state of pain is one that can be shared among many, whether they are human or...