Can there be a categorical, reasonably non-rejectable grounding of human rights? The paper engages a recent attempt to provide such a grounding, namely, Forst???s ???reflexive??? account. On this account, moral-political validity claims commit us to a constructivist requirement of reciprocal and general acceptability, while this requirement both commits us to accord to others a right to justification and allows for a justification of other human rights. The paper grants the substantive implications of this requirement, but takes issue with the claim that it is reasonably non-rejectable. I argue that this requirement cannot be established reflexively in Forst???s sense, and this is for reasons that mark general limitations of reflexive, pres...