The explanatory gap refers to the lack of concepts for
understanding “how it is that . . . a state of consciousness
comes about as a result of irritating nervous tissue.” By
assuming that there are colours in the outside world, Block needlessly
widens this gap and Lycan and Kitcher simply fail to see the gap. When
such assumptions are abandoned, an unnecessary and incomprehensible
constraint disappears. It then becomes clear that the brain can use
its own neural language for representing aspects of the outside world.
While this may not close the gap, it becomes clearer where we need new
concepts.
