Dialogue (sometimes spelled dialog in American English) is a written or spoken conversational exchange between two or more people, and a literary and theatrical form that depicts such an exchange. As a philosophical or didactic device, it is chiefly associated in the West with the Socratic dialogue as developed by Plato, but antecedents are also found in other traditions including Indian literature.
The term dialogue stems from the Greek διάλογος (dialogos, conversation); its roots are διά (dia: through) and λόγος (logos: speech, reason). The first extant author who uses the term is Plato, in whose works it is closely associated with the art of dialectic. Latin took over the word as dialogus.
Dialogue as a genre in the Middle East and Asia dates back to ancient works, such as Sumerian disputations preserved in copies from the late third millennium BC, Rigvedic dialogue hymns and the Mahabharata.
In the West, Plato (c. 437 BC – c. 347 BC) has commonly been credited with the systematic use of dialogue as an independent literary form. Ancient sources indicate, however, that the Platonic dialogue had its foundations in the mime, which the Sicilian poets Sophron and Epicharmus had cultivated half a century earlier. These works, admired and imitated by Plato, have not survived and we have only the vaguest idea of how they may have been performed. The Mimes of Herodas, which were found in a papyrus in 1891, give some idea of their character.
Plato further simplified the form and reduced it to pure argumentative conversation, while leaving intact the amusing element of character-drawing. By about 400 BC he had perfected the Socratic dialogue. All his extant writings, except the Apology and Epistles, use this form.
Following Plato, the dialogue became a major literary genre in antiquity, and several important works both in Latin and in Greek were written. Soon after Plato, Xenophon wrote his own Symposium; also, Aristotle is said to have written several philosophical dialogues in Plato's style (of which only fragments survive).