This paper focuses on a particular construction of the self, a paradigmatic topic of Renaissance literature, in Giordano Bruno’s dialogue La cena de le Ceneri – The Ash Wednesday Supper (1584). In order to do so, it looks at the text from a ‘performative’ point of view, using a new method apt to reveal possibilities of the dialogue as a genre so far rather neglected in Bruno scholarship. The essay interprets the dialogue as a mise en scène of the author’s persona, the ‘Nolan’, an attempted ‘self-fashioning’ as a philosophic-scientific authority meant to underpin his Copernican cosmology. Through the Nolan, Bruno makes claims to absolute truth within a genre often correlated with a pluralistic concept of truth. Therefore he ‘performatizes’ his argumentation – Bruno relies less on discursively justifying his claims than on making them immediately evident – by introducing motifs of comedy and epic poetry into his text. In the end, however, the form of his dialogue itself seems to jeopardize the Nolan’s professed authority, creating ambiguity.