Abstract One of Japan’s most versatile scholars of film, television, and manga (comic books), Yomota Inuhiko (1953–) made a deep impact on Manga Studies, where he engaged in a form of manga analysis commonly called “expression theory” (hyōgen-ron). In the present translated twin essays from Yomota’s now-classic study, The Principles of Manga (Manga Genron, 1994), he demonstrates his awareness of the possibilities of applying a linguistic lens to the study of Japanese comics. In Part One, Yomota explores the idea of onomatopoeia in manga, considering how they are very much cultural constructions that can be difficult to translate into other languages. In Part Two, Yomota delves deeper into the way onomatopoeia appear on the page, often creating impossible-to-utter expressions but ones easily understood nonetheless by readers. While there is already a great deal of research on onomatopoeia mimetics in spoken Japanese, Yomota here expounds on how manga artists have invented new ways of employing onomatopoeia outside of these established patterns in the spoken language. He gives clear examples of the evolution and representation of mimetics in manga, discusses several key features of comic-book mimetics, and makes a clear argument that they have spurred the evolution of modern-day manga.