We examine the interaction of two phonological notions: Greek letter variables,
(α-notation), and natural classes in the context of Logical Phonology. The conclusions we reach hold for any theory that attempts to develop a precise mapping between phonological notation and mental processes/representations. By keeping the Greek variables in the grammar, rather than treating them as metalanguage variables, we predict where learners will generalize rules. Our “variable subsumption” model is a theory of what counts as a natural class.