A standard view in the philosophy of mind is that there are two very different concepts of the mental: the phenomenal and the functional. Terms that express phenomenal concepts refer to the way that mental states feel from the first-person perspective. Terms that express functional concepts refer to the causal roles that mental states play in relation to ones behavior and other mental states. Many ordinary mental terms apply to mental phenomena that have both phenomenal properties and functional properties—terms like "pain," "perceive," and "desire." Philosophers often claim that terms like these conflate distinct phenomena: really, there are two concepts of pain, and two kinds of mental states they apply to, that the ordinary use of the term "pain" conflates. The same is true of other such terms. Although their phenomenal and functional uses reliably coincide, they are conceptually distinct (we can, supposedly, imagine one existing without the other and vice versa), and so scientists and philosophers should not treat them as the same. Call this view the "two-concept framework."
While I accept that phenomenal and functional properties may be distinct, I am convinced that the two-concept framework is largely unjustified. One line of criticism that the two-concept framework supports is the charge that scientists conflate the functional concept expressed by the term "consciousness" with the phenomenal concept express by the term (see Ned Block's "On a confusion about a function of consciousness"). The argument, which philosophers rarely make explicit, is something like this:
- Scientists offer theories of consciousness that are clearly aimed at phenomenal mental states but then go on to offer (broadly construed) functionalist theories of consciousness. So either scientists confuse the phenomenal concept expressed by the term "consciousness" with the functional concept expressed by the term, or they believe that phenomenal mental states can be explained by functional mental states.
- Phenomenal mental states cannot be explained in terms of functionally specified mental states (the explanatory gap).
- So either scientists are obviously mistaken or they conflate the different concepts expressed by the term "consciousness" (from 1 and 2).
- So scientists conflate the different concepts expressed by the term "consciousness" (3 and the principle of charity).
In short, scientists are either obviously mistaken or subtly confused, and the principle of charity recommends the latter interpretation. The crux of the argument is premise three, the explanatory gap. The explanatory gap is the special difficulty of explaining how mental states with phenomenal character arise from the material states of one's nervous system. The trouble with this argument, as I argue in my dissertation, is that the explanatory gap isn't obvious, since many philosophers and scientists deny its existence. Not only that, the premise is question-begging in the present case, since many of the scientists defending these theories explicitly reject the explanatory gap.
But setting those issues aside, let's assume that scientists do conflate phenomenal and function properties and let's suppose that they accept the explanatory gap. Does it follow that the scientists' theories can't be aimed at conscious mental states with phenomenal properties? I think the answer is still no. The reason is that, so far as I can tell, philosophers have provided little reason to think that there are two distinct kinds of mental states, the phenomenal and the functional. Since the two reliably coincide, it is entirely reasonable to suppose that they are features of one and the same kind of mental state, even if one accepts that there is an explanatory gap. If that is right, then scientists can offer theories of consciousness while neither bridging the explanatory gap or nor denying its existence. In setting out to give a theory of time, one is likely to include one's initial description of time the so-called "arrow of time," the fact that universe is always moving (through time) from states of lower entropy to states of higher entropy. Theories of time, however, have yet to be explain the arrow of time. Should we conclude, then, that none of these theories are really theories of time, or that whatever explains the arrow of time must be something over and above time itself? Probably not.
Further, the assumption that phenomenal and functional mental states are distinct, separable kinds of states leads to the problem I discussed in my last post, effectively blocking (from the philosophical perspective) the possibility of scientific progress on consciousness. Some of have called this the "harder" problem of consciousness, and if what I argued there is right, there is reason to think that the problem is even worse than philosophers thought.
I argue in my dissertation that the concept of consciousness is a cluster concept and that, despite its many distinct features, there is good reason to believe that scientists are converging on a common target of explanation. It cannot, and should not, be boiled down to phenomenal properties alone or functional properties alone. Although many philosophers have chosen to study the phenomenal and functional properties of consciousness separately from one another, scientists see them as two sides of the same coin. And no, this doesn't mean that scientists are conflating different "concepts of consciousness," as so many philosophers are convinced.