Language is a system of symbols based on relations, among which syntagmatic and paradigmatic relations are the most universal and important ones. Paradigmatic relations are also called associative relations because they represent relationship between individual element is specific environments with such elements in the memory which can potentially replace them. Paradigmatic relations are based on the criteria of selection and distribution of linguistic elements, and are, for example, the basis for establishing the phoneme inventory of a language through the construction of minimal pairs, the replacement of sounds in an otherwise constant environment that leads to a difference in meaning.