For a long time, Chinese characters have been considered merely as a tool for recording the spoken language. However, in certain contexts, Chinese characters can also convey trans-glossematic information, e.g. information incompatible with the character that is used to record its glosseme can be conveyed by some component of the character or simply by the form of the character; information that is not within the semantic category of the corresponding glosseme can be conveyed by an altered character. In fact, Chinese characters, consisting of a set of plane symbols, function as a self-contained whole, which work well with the Chinese language and keep their own features at the same time. Because of this trans-glossematic communication function, Chinese characters are not a mere copy of the Chinese language. On the contrary, they can convey messages on their own when needed.
This trans-glossematic function is determined by the origin and structural features of Chinese characters. In the very beginning, the lack of correspondence between characters and glossemes, as well as the principle of representing an object by a character form that resembles it, influenced the way people understood and used the characters. The structural feature of Chinese characters, i.e. the planar composition of the characters, has rendered the alternation of characters and the separation of components possible. Therefore, there are a diversity of ways to express meaning with Chinese characters: by using just the form of a character, piecing or separating components, re-analyzing characters, adding or reducing strokes, moving strokes, or altering character forms.
Expression through the use of character forms and structures is a special rhetorical device. Here we call it the rhetoric of Chinese characters.