There are two broad classes of empirical theories of consciousness, which I will call the biological and the functional. The biological approach is based on empirical correlations between experience and the brain. For example, there is a great deal of evidence that the neural correlate of visual experience is activity in a set of occipetotemporal pathways, with special emphasis on the infero-temporal cortex. The functionalist approach is a successor of behaviorism, the view that mentality can be seen as tendencies to (...) emit certain behavioral outputs given certain sensory inputs. The trouble with behaviorism is that it did not allow that mental states were causes and effects, but functionalists do allow this. They characterize consciousness in terms of its causal role: the causal influence on it from inputs and other mental states, and its causal efficacy with respect to other mental states and behavior. The central idea of functionalism is a proposal about the concept of consciousness, but scientific functionalists have filled the view in with empirical details—the idea is that a representation is conscious if it is broadcast in a global neuronal workspace. The functional approach says consciousness is a role, whereas the biological approach says consciousness is a realizer of that role. For example, one could take solubility to be a role—dissolving in certain circumstances—or, as with the biological view of consciousness, the physico-chemical configuration that has that role. The. (shrink)

The functionalist view of the nature of the mind is now widely accepted. Like behaviorism and physicalism, functionalism seeks to answer the question "What are mental states?" I shall be concerned with identity thesis formulations of functionalism. They say, for example, that pain is a functional state, just as identity thesis formulations of physicalism say that pain is a physical state.