 Here it might help to compare the sighted subject with a conscious subject for whom things are just the same from the inside, but who fails to see any \(X\) because she is hallucinating. If the sighted subject and the hallucinating subject are equally justified in believing there is an \(X\) to the left, visual experience might be a better candidate than seeing to explain the epistemic symmetry between the sighted and the hallucinating subjects.