of this self-referential gift-giving appears in the Stefaneschi Triptych in the Vatican Museum, which features Cardinal Giacomo Gaetani Stefaneschi as the giver of the altarpiece. Critical theory and art history In Western art history, mise en abyme is a formal technique in which an image contains a smaller copy of itself, in a sequence appearing to recur infinitely; "recursion" is another term for this. The modern meaning of the phrase originates with the author André Gide who used it to describe self-reflexive embeddings in various art forms and to describe what he sought in his own work. As examples, Gide cites both paintings such as Las Meninas by Diego Velázquez and literary forms such as William Shakespeare's use of the "play within a play" device in Hamlet, where a theatrical company presents a performance for the characters that illuminates a thematic aspect of the play itself. This use of the phrase mise en abyme was picked up by scholars and popularized in the 1977 book Le récit spéculaire. Essai sur la mise en abyme by Lucien Dällenbach. Literature and film Mise en abyme occurs in a text when there is a reduplication of images or concepts referring to the textual whole. Mise en abyme is a play of signifiers within a text, of sub-texts mirroring each other. This mirroring can attain a level where meaning may become unstable and, in this respect, may be seen as part of the process of deconstruction. The film-within-a-film, where a film contains a plot about the making of a movie, is an example of mise en abyme. The film being made within the film refers, through its mise en scène, to the real film being made. The spectator sees film equipment, stars getting ready for the take, crew sorting out the various directorial needs. The narrative of the film within the film may directly reflect the one in the real film. An example is La Nuit américaine (1973) by François Truffaut. In film, the meaning of mise en abyme is similar to the artistic definition, but also includes the idea of a "dream within a dream". For example, a character awakens from a dream and later discovers that they are still dreaming. Activities similar to dreaming, such as unconsciousness and virtual reality, also are described as mise en abyme. This is seen in the film eXistenZ where the two protagonists never truly know whether