The Amphiboly in the Third Horn: A Structural Equivocation in the Agrippan and Münchhausen Trilemmas

The Agrippan Trilemma holds that any attempt to justify a claim must terminate in infinite regress, circularity, or dogmatic stopping. For over two thousand years, this argument has been treated as exhaustive: every epistemological framework concedes one horn rather than defeating the Trilemma outright. This paper identifies a previously undiagnosed structural amphiboly in the third horn that invalidates the Trilemma’s claim to universality. Both the ancient formulation (Sextus Empiricus, Outlines of Pyrrhonism I.15) and the modern reformulation (Hans Albert, Treatise on Critical Reason, 1968) conflate two non-equivalent propositions: that a justificatory chain terminates (Reading A), and that it terminates at a point with no independent grounds for trust (Reading B). Reading A is a tautology true of all termination. Reading B is the epistemically damaging claim the Trilemma requires but never argues for. The slide from A to B is demonstrated textually in both canonical formulations. Once the two readings are distinguished, the third horn applies only to termination that is genuinely unchecked, not to termination as such. The Trilemma’s conclusion, that justified knowledge is impossible, depends on the conjunction of all three horns. Since the third horn rests on a conflation it does not acknowledge and cannot defend, the conclusion does not follow universally.