In a short sketch, the author presents broadly the problems of the fifth part of the art of rhetoric, that is, pronunciation (actio), as an area in which the similarities and differences between rhetoric and acting are revealed — a topic which is worthy of a separate monograph. The first part of the text is devoted to a brief ordering of these issues, while the second part constitutes an analysis and interpretation of fragments of two ancient sources that can be used to describe the separation of the art of oratory and the art of acting in the history of Graeco-Roman rhetoric. These are: Book III of Aristotle’s Rhetoric and Book I of the treatise On the orator by Marcus Tullius Cicero.