Mutual exclusivity and synonymy avoidance: Two sides of the same coin

The principle of ‘mutual exclusivity’ is a well-studied feature of early L1 language acquisition and refers to learners’ assumption that an entity has a single unique label. This assumption makes it hard for children to map synonyms and hypernyms to the same entity. Similarly, in morphological theory, linguists such as Kiparsky (1982) and Giegerich (2001) observe ‘synonymy avoidance’, a principle which is sometimes evident through blocking and sometimes a semantic divergence between processes that would usually result in synonyms (Pinker, 1999; Plag, 2003). Thus the principle of mutual exclusivity during word learning disfavours adding several labels for one entity and synonymy avoidance disfavours creating new synonymous forms. This presentation suggests that these two principles can be treated as results of the same underlying function, which is active in different ways in the speaker depending on that person’s stage of language learning. In young learners this principle aids word learning since it allows children to extrapolate the names for new objects when set against ones they know (Merriman & Bowman, 1989). Whereas, in older speakers, this principle lives on as a residue and adheres to language simplicity on the one hand, by preventing synonyms, and complexity on the other, since it allows certain morphological processes to apply as long as the outputs are distinct in meaning. How this principle works as a language learning heuristic and how it can give rise to synonymy avoidance is discussed with reference to blocking and bilingualism (Frank & Poulin-Dubois, 2007).