Even if spectrum inversion of various sorts is possible, spectrum inversion without a difference in representation is not. So spectrum inversion does not pose a challenge for the intentionalist thesis that, necessarily, within a given sense modality, if two experiences are alike with respect to content, they are also alike with respect to their phenomenal character. On the contrary, reflection on variants of standard cases of spectrum inversion provides a strong argument for intentionalism. Depending on one’s views about the possibility (...) of spectrum inversion, the impossibility of spectrum inversion without a difference in representation can also be used as an argument against a variety of reductive theories of mental representation. (shrink)

A version of the inverted spectrum thought experiment that disconfirms functionalism for the case of humans’ color experiences has typically been thought to require a certain kind of balancing act. What one needs, it has typically been thought, is a mapping of color experiences onto other color experiences that preserves the similarity and difference relationships among those experiences and the aspects of perceived colors underlying those similarities and differences. However, there are good reasons for being suspicious about whether that is (...) possible when the palette of color experiences is that available to humans with normal vision. The new version of the thought experiment constructed here doesn’t depend on preserving those relationships. I argue that there is a coherent, metaphysically possible scenario in which two human color experiences—any two—can be seen to be functionally equivalent. The upshot is that functionalism fails for all human color experiences. (shrink)