This article examines Abu Hayyan Al-Gharnati’s, as presented in his works Al-Tahseel wa al-Tadhyeel and Irtishaf al-Darab. It employs a methodological approach to analyze and interpret his theoretical and logical principles, focusing on grammar as a study of linguistic entities and their rules across three levels: propositional, syntactic, and semantic.

Abu Hayyan classifies nouns, verbs, and particles based on intrinsic semantic definitions, rejecting incidental properties like attribution. He distinguishes between verb forms (past, present, imperative) and structures (past, present, future), applying operator theory to explain case marking as an existential effect linked to a word’s morphological stability.

Additionally, he views the ordering of case markers—nominative, accusative, genitive—as aesthetic rather than fixed. His syntactic analysis emphasizes subject-predicate attribution through verbal and nominal structures, which drive nominative case usage, while direct objects and genitive constructions produce accusative and genitive cases. This framework sheds light on his innovative approach to grammatical theory.