Abstract: The adverbial SELF switches its meanings in many languages. In the context of Relevance Theory, this paper argues that, for the Mandarin adverbial ziji, its different semantic behaviors in specific contexts are not caused by its “polysemous” nature, but by its various procedural encoding within the framework of Relevance Theory. In other words, there is only one adverbial ziji in Mandarin, encoding the conceptual meaning of “exclusion”, but it can convey different surface meanings in different contexts. When encoding a shifting +SHIFT procedural meaning, ziji helps the hearer exclude the alternatives of the focused element as the agent of the event, producing a cognitive effect of contextual contradiction and guides the hearer to obtain the contextual meaning of “exclusion”; when encoding both continuative +CONT and shifting +SHIFT procedural meanings, ziji is often used to exclude the alternatives as the current topic in the context, yielding respectively the cognitive effects of contextual strengthening and contextual contradiction and helps the hearer derive the “inclusive” meaning. By “exclusion”, the adverbial ziji can output various cognitive effects and finally achieve its intensification.