On widening the explanatory gap

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 that 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.