The aim of this paper is to provide a model that allows the representation and analysis of circularity in ethotic structures, i.e. in communication structures related to the speaker's character and in particular, his credibility. The paper studies three types of cycles: in self-referential sentences, embedded testimony and ethotic begging the question. It is shown that standard models allow the reconstruction of the circularities only if those circular utterances are interpreted as ethotic arguments. Their alternative, assertive interpretation requires enriching the existing models with a purely ethotic component related to the credibility of the performer of any (not necessarily argumentative) speech act. © 2012 The Author(s).