The knowability principle, formulated without restrictions, asserts that all true statements are knowable. The problem is that it is subject to many objections in this formulation, and therfore it is necessary to restrict the principle. This article shows that even under these restrictions some true statements are also unknowable, and thus shows that the knowability principle, even in its most restricted form, is false. The statements in question are statements that affirm or deny a type identity between qualia of different individuals. Finally, some arguments that can be used to defend the knowability principle are examined and refuted.
Knowability principle; Qualia; Verification principle