 On Kvanvig’s diagnosis, the problem with Fitch’s reasoning is that when he substituted the conjunction \(p \wedge \neg Kp\) for \(p\) in KP (at line 2 of the result), he did not stop to determine whether \(p \wedge \neg Kp\) is rigid. Kvanvig maintains that \(p \wedge \neg Kp\) is not rigid. So Fitch’s result is fallacious owing to an illicit substitution into a modal context. But we may reconstrue \(p \wedge \neg Kp\) as rigid. And when we do, the paradox evaporates.