noun
theory of written language; grammatology
Academic term for the study of writing systems, their structure, history, and relationship to spoken language.
彼は文字論の観点から漢字の成り立ちを研究している。
He researches the origins of kanji from the perspective of grammatology.
文字学 is a near-synonym, but 文字論 often implies a more theoretical or philosophical approach.
Compound of 文字 (moji, 'character, letter') and 論 (ron, 'theory, discourse'). The term is a modern academic coinage.