of "a-signifying signs"). In his The Theatre and its Double (1938), Artaud compared this interaction to the way in which a snake charmer communicates with a snake, a process which he identified as "mimesis"—the same term that Aristotle in his Poetics () used to describe the mode in which drama communicates its story, by virtue of its embodiment by the actor enacting it, as distinct from "diegesis", or the way in which a narrator may describe it. These "vibrations" passing from the actor to the audience may not necessarily precipitate into significant elements as such (that is, consciously perceived "meanings"), but rather may operate by means of the circulation of "affects". The approach to acting adopted by other theatre practitioners involve varying degrees of concern with the semiotics of acting. Konstantin Stanislavski, for example, addresses the ways in which an actor, building on what he calls the "experiencing" of a role, should also shape and adjust a performance in order to support the overall significance of the drama—a process that he calls establishing the "perspective of the role". The semiotics of acting plays a far more central role in Bertolt Brecht's epic theatre, in which an actor is concerned to bring out clearly the socio historical significance of behaviour and action by means of specific performance choices—a process that he describes as establishing the "not/but" element in a performed physical "gestus" within context of the play's overal "Fabel". Eugenio Barba argues that actors ought not to concern themselves with the significance of their performance behaviour; this aspect is the responsibility, he claims, of the director, who weaves the signifying elements of an actor's performance into the director's dramaturgical "montage". The theatre semiotician Patrice Pavis, alluding to the contrast between Stanislavski's 'system' and Brecht's demonstrating performer—and, beyond that, to Denis Diderot's foundational essay on the art of acting, Paradox of the Actor (–78)—argues that: Elements of a semiotics of acting include the actor's gestures, facial expressions, intonation and other vocal qualities, rhythm, and the ways in which these aspects of an individual performance relate to the drama and the theatrical event (or film, television programme, or radio broadcast, each of which involves different semiotic systems) considered as a whole. A semiotics of acting recognises that all forms of acting involve conventions and codes by means of which performance behaviour acquires significance—including those approaches, such as Stanislvaski's or the closely related method