The iconicity of grammar: Isomorphism and motivation

Although linguistic signs in isolation are symbolic, the system or grammar which relates them may be diagrammatically iconic in two ways: (a) by isomorphism, a bi-unique correspondence tends to be established between signans and signatum; (b) by motivation, the structure of language directly reflects some aspect of the structure of reality. Isomorphism is so nearly universal that deviations from it require explanation. Motivation, although widespread, establishes a typology of languages, as indicated in Saussure's Cours. The evidence of artificial taboo languages suggests that degree of motivation co-varies inversely with the number of ‘prima onomata’ in the lexicon.