On Explanation in the Cognitive Sciences: Competence, Idealization, and the Failure of the Classical Cascade

The ‘classical cascade’ of explanation through three ‘levels of description’ is a central methodological underpinning of the cognitive sciences. I argue, however, that it often fails to provide adequate explanations, in particular in conjunction with competence theories. This failure originates in the idealizations in competence descriptions, which either ‘block’ the cascade, or produce a successful cascade which fails to explain cognition.