 The unification account of explanation has been defended within a more detailed cognitive and pragmatist approach. The key is to think of explanations as question-answer episodes involving four elements: the explanation-seeking question about \(P, P\)?, the cognitive state \(C\) of the questioner/agent for whom \(P\) calls for explanation, the answer \(A\), and the cognitive state \(C+A\) in which the need for explanation of \(P\) has disappeared. A related account models unity in the cognitive state in terms of the comparative increase of coherence and elimination of spurious unity—such as circularity or redundancy (Schurz 1999).  Unification is also based on information-theoretic transfer or inference relations. Unification of hypotheses is only a virtue if it unifies data. The last two conditions imply that unification yields also empirical confirmation. Explanations are global increases in unification in the cognitive state of the cognitive agent (Schurz 1999; Schurz and Lambert 1994).