Congruence measurement in inflectional system of Persian language on the basis of natural morphology theory

Adopting a theory and data-based research via introducing natural morphology theory, this article, tries to study inflectional system of Persian language on the basis of congruity –system principle which is one of the components of dependent-system theory. The authors have stated unique features of inflectional affixes. Then, on the basis of five properties of this principle (occurrence of categorical systems and categories, occurrence of base form inflection or stem inflection, separate or combined symbolization of categories, number and manner of formal distinctions in the paradigm, occurrence of marker types related to the categorical system involved, and presence or absence of inflectional classes), the congruity of inflectional affixes of the Persian language has been measured. For this purpose these affixes have been analyzed in three macro classes: noun, verb, and adjective. On the basis of this principle adjective affixes are more congruous and uniform, but noun affixes are less natural.