There is much critical dispute about who the author of On the Sublime was and when he lived. The earliest surviving copy of the text, from the medieval period, attributes On the Sublime to “Dionysius or Longinus.” There was a famous rhetorician and philosopher named Cassius Longinus (213-273 AD), who was born in Syria and taught in Athens; there was also a Greek rhetorician and historian named Dionysius of Halicarnassus (first century AD). Whether either of these writers was the author of On the Sublime, or whether the author was a third person named “Dionysius Longinus” has been the subject of extensive speculation. Because the author is unknown, he is sometimes also referred to as Pseudo-Longinus.

The text offers little evidence to help solve the authorship mystery. The author describes his work as a response to a treatise by Caecilius of Calacte, who lived in the first century, but this does not prove that On the Sublime was written then, since writers of that era frequently commented on older works. The references to a decline in eloquence in Chapter 44 are not a sure clue, either, since many writers made this lament over several centuries.

What is certain is that the author of On the Sublime has strongly influenced Western thinking about literature, aesthetics, and criticism for many centuries.