Some mental states are such that there is ‘something that it is like’ to be in that state. There is something that it is like to have a bad toothache; there is something that it is like to see red; there is something that it is like to have an itch. (Maybe every mental state is such that there is something that it is like to be in that state; this is controversial. But it should be uncontroversial that at least some mental states, like the ones listed above, are like this.)
The word ‘qualia’ is used in philosophy to stand for the aspects of mental states that contribute to what it is like to be in that mental state. Often, this term does more harm than good, since it makes it sound as though, in addition to these mental states, there are mysterious items, qualia, hanging around. As we’ll be using the notion, you needn’t assume anything like this. Talk about ‘qualia’ will be just a loose way of talking about mental states which are such that there is something that it is like to be in that mental state.
Since functionalism purports to be a theory of mental properties in general, it should have something to say about the mental states listed above, which have qualia. In particular, given the description of functionalism we gave last class, there must be, associated with each such mental property, a role which is such that something has the mental property if and only if it has some state which plays that role.
Block, in §1.2 of ‘Troubles with functionalism’, objects to functionalism on the grounds that it predicts that certain things will have mental properties which in fact lack those mental properties. This is what he means by saying that functionalism is guilty of ‘liberalism.’
Example 1: the ‘humunculi-headed robot’ (215).
Example 2: the Chinese nation:
“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 a specially designed twoway 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 ...
It is not at all obvious that the China-body system is physically impossible. It could be functionally equivalent to you for a short time, say an hour.” (215-6)
Why is this example supposed to pose a problem for functionalism? How could a functionalist respond?
Zombies (of the philosophical kind) are behavioral and/or physical duplicates of conscious beings that, however, lack conscious experience. Here is one prominent recent discussion of zombies:
“So let us consider my zombie twin. This creature is molecule for molecule identical to me, and identical in all the low-level properties postulated by a completed physics, but he lacks conscious experience entirely. ...To fix ideas, we can imagine that right now I am gazing out the window, experiencing some nice green sensations ...
What is going on in my zombie twin? ...He will certainly be identical to me functionally: he will be processing the same sort of information, reacting in similar way to inputs, with his internal configurations being modified appropriately and with indistinguishable behavior resulting. ...It is just that none of this functioning will be accompanied by any real conscious experience. ...There is nothing that it is like to be a zombie.
This sort of zombie is quite unlike the zombies found in Hollywood movies, which tend to have significant functional impairments. ...as Block (1995) points out, it is reasonable to suppose that there is something it tastes like when they eat their victims. ...
...
I confess that the logical possibility of zombies seems ...obvious to me. A zombie is just something physically identical to me, but which has no conscious experience — all is dark inside.” (Chalmers, The Conscious Mind, pp. 95-6)
How could zombies pose a challenge to functionalism?
(For more information on zombies, philosophical and otherwise, check out ‘Zombies on the web’ at http://consc.net/zombies.html.)
The above cases are ones in which a functional duplicate of a creature which has states with certain qualia lacks those qualia. A different sort of problem for functionalism is posed by cases in which two creatures are functionally identical, and each have qualia, but have different qualia. Examples of ‘spectrum inversion’ are like this. This kind of example was introduced into the philosophical literature by John Locke:
“Neither would it carry any Imputation of Falsehood to our simple Ideas, if by the different Structure of our Organs, it were so ordered, That the same Object should produce in several Mens Minds different Ideas at the same time; v.g. if the Idea, that a Violet produced in one Mans Mind by his Eyes, were the same that a Marigold produces in another Mans, and vice versa. For since this could never be known: because one Mans Mind could not pass into another Mans Body, to perceive, what Appearances were produced by those Organs; neither the Ideas hereby, nor the Names, would be at all confounded, or any Falsehood be in either. For all Things, that had the Texture of a Violet, producing constantly the Idea, which he called Blue, and those which had the Texture of a Marigold, producing constantly the Idea, which he as constantly called Yellow, whatever those Appearances were in his Mind; he would be able as regularly to distinguish Things for his Use by those Appearances, and understand, and signify those distinctions, marked by the Names Blue and Yellow, as if the Appearances, or Ideas in his Mind, received from those two Flowers, were exactly the same, with the Ideas in other Mens Minds.” (Essay on Human Understanding, II.xxxii.15)
Why is this supposed to pose a problem for functionalism? Could two people, spectrum inverted relative to each other, really be functional duplicates?