The occurrence of speech is dependent on the presence of three principal factors: speaker, addressee and discourse. In the past, literate people were few in numbers and there was no means of reproducing texts; consequently, communication between the speaker and the addressee was oral. In modern times, as a result of the rise in literacy and the invention of the means of reproducing texts this communication occurs in a written mode. The author produces the text in the absence of readers, of whose knowledge and emotional condition he has no information. Likewise, the reader reads the text in the absence of the author and usually with no information about the latter’s emotional condition or knowledge. If we take communication to be a kind of dialogue, it could then be argued that the author’s dialogue with the reader takes place at the moment of the text’s production and in the reader’s absence, and the reader’s dialogue with the text occurs in the author’s absence. In view of the four factors making up the context for the text’s production and consumption, the radical shift in man’s view about the universe, and the transformation of literary communication from an oral to a written mode which allows the reader to contemplate and comprehend the text, the conventional conditions and aesthetic devices of literature, too, undergo a radical change and, among other things, rhetoric, which was an attribute of the speaker and speech, becomes the addressee’s attribute and his interpretation of the text. For in such circumstances, the text breaks itself free from the authority of the author and comes under the control of the reader. In its first section, this paper discusses various Persian poetical genres in the classical period, the effect of the kind of addressees on the type of discourse and the speaker, the relation between content and form, and the effect of written communication and the production of the text in the absence of the reader. In the second section, a poem by the modern Iranian poet Nima Yushij is analysed as an example of how rhetoric is shifted from the speaker/author to the addressee/reader as a consequence of the new communication situation between the author and the reader.