Absent qualia problem
Imagine a rose smelling experience can be instantiated through complex, functionally organised interactions among the entire population of China. Functionalists must argue that the rose-smelling eperience exists, but the qualia would be absent.
The result seems counterintuitive.
Ned Block (1978).
Notes: although there are different examples of the absent qualia problem, the rose smelling experience example is often referred to as the absent qualia problem.
If the conscious experience of the smell of a rose is actually a complex functional interaction among other states, inputs, and outputs, then such an experience could be instantiated in a variety of mediums. The entire population of China could instantiate the correct functional interactions necessary for a conscious experience and yet there would be (it seems) no conscious rose-smelling experience created. Therefore, functionalism is false.
The Block argumentBlock puts the claim this way:
"Suppose we convert the government of China to functionalism, and we convince its officials to realize a human mind for an hour. We provide each of the billion people in China (I chose China because it has a billion inhabitants) with specially designed two way radio that connects them in the appropriate way to other persons and to the artificial body mentioned in the previous example. We replace each of the little men with a citizen of China plus his radio. Instead of a bulletin board, we arrange to have letters displayed on a series of satellites placed so that they can be seen from anywhere in China.
"The system of a billion people communicating with one another plus satellites plays the role of an external "brain' connected to the artificial body by radio. There is nothing absurd about a person being connected to his brain by radio" (N. Block, 1991, p. 216).
Block concludes:
"What makes the homunculi-headed system (count the two systems as variants of a single system) just described a prima facie counterexample to (machine) functionalism is that there is prima facie doubt whether it has any mental states at all--especially whether it has what philosophers have variously called 'qualitative states,' 'raw feels,' or 'immediate phenomenological qualities'" (N. Block, 1991, p. 217)."
References
Block, Ned. 1991. Troubles with functionalism. In
The Nature of Mental States, edited by David Rosenthal, pp. 211-228. New York: Oxford University Press. Originally in
Minnesota Studies in the Philosophy of Science, volume IX, 1978, edited by C. Wade Savage, p. 261-326. Minneapolis: University of Minnesota Press.