The classical unities, Aristotelian unities, or three unities represent a prescriptive theory of dramatic tragedy that was introduced in Italy in the 16th century and was influential for three centuries. The three unities are: unity of action: a tragedy should have one principal action. unity of time: the action in a tragedy should occur over a period of no more than 24 hours. unity of place: a tragedy should exist in a single physical location. History Italy In 1514, author and critic Gian Giorgio Trissino (1478 – 1550) introduced the concept of the unities in his blank-verse tragedy, Sofonisba. Trissino claimed he was following Aristotle. However, Trissino had no access to Aristotle's most significant work on the tragic form, Poetics. Trissino expanded with his own ideas on what he was able to glean from Aristotle's book, Rhetoric. In Rhetoric Aristotle considers the dramatic elements of action and time, while focusing on audience reception. Poor translations at the time resulted in some misreadings by Trissino. Trissino's play Sofonisba followed classical Greek style by adhering to the unities, by omitting the usual act division, and even introducing a chorus. The many Italian playwrights that came after Trissino in the 16th Century, also wrote in accordance to the unities. However, according to The Cambridge Guide to Theatre, the imitation of classical forms and modes had a deadening effect on Italian drama, which became "rhetorical and inert". None of the 16th century tragedies that were influenced by the rediscovery of ancient literature have survived except as historic examples. One of the best is Pietro Aretino's Orazia (1546), which nevertheless is found to be stiff, distant and lacking in feeling. In 1570 the unities were codified and given new definition by Lodovico Castelvetro (ca. 1505–1571) in his influential translation and interpretation of Aristotle’s Poetics, Poetica d'Aristotele vulgarizzata e sposta ("The Poetics of Aristotle translated in the Vulgar Language and commented on"). Though Castelvetro’s translations are considered crude and inaccurate, and though he at times altered Aristotle's meanings to make his own points, his translations were influential and inspired the vast number of scholarly debates and discussions that followed all through Europe. France One hundred and twenty years after Sofonisba introduced the theory to Italy, it then introduced the concept once again, this time in France with a translation by Jean Mairet. Voltaire said that the Sophonisba of Mairet had "a merit which was then entirely