It is customary to use the present tense when discussing a literary work:
Othello is a play by Shakespeare. It begins on a street in Venice, where Roderigo and Iago are arguing.
Some of the themes of Othello are racism, love, jealousy, and betrayal.
Like other Shakespearean tragedies, Othello has five acts.
The play ends with Othello’s murder of Desdemona and with the revelation of Iago’s motives.
Likewise, use the present tense to describe the actions of characters and the movement of plot:
In act 3 Iago persuades Othello that there is reason to doubt Desdemona’s faithfulness, and in the final act Othello confronts Desdemona and then strangles her to death.
The rationale for using the present tense when discussing a work is that the work exists in the present just as it existed earlier: Othello always has five acts and always ends with the same actions.
The principle applies to works of all sorts, from literary criticism to films to websites:
William Hazlitt’s Characters of Shakespeare’s Plays contrasts expressions of passion and violence in Othello and Macbeth.
A 1965 film version of Othello stars Laurence Olivier.
The blog Bard Film analyzes references to Shakespeare in popular films.
By extension, you may also use the present tense when the subject is not the work itself but the work’s author, if the work is implied. In the following examples, “in Othello” is implied:
[In Othello] Shakespeare gives Iago, an archetypal villain, an important role.
By identifying Othello as a Moor, Shakespeare introduces both racial and religious issues [in Othello].
Acceptable Uses of the Past Tense
If you’re primarily discussing the historical context of a work, however, use the past tense:
By identifying Othello as a Moor, Shakespeare introduced both racial and religious issues to early modern playgoers.
Use care when choosing between the past and present tense. A good rule of thumb is to consider whether the principal context of your discussion is textual or historical.
When the context is clearly historical, the choice of the past tense is obvious:
Othello was first performed in 1604, at Whitehall Palace in London.
Shakespeare composed Othello about fifteen years after Marlowe wrote Tamberlaine.
Aim for Consistency
Above all, aim for consistency and try to avoid frequent shifts in tense, which can be jarring for readers. It’s easy to shift tenses without realizing it. Here’s an example that uses tenses inconsistently:
For the plot of Othello, Shakespeare adapts a sixteenth-century Italian tale, while Christopher Marlowe based his play Tamberlaine on the life of an Asian emperor.
In this sentence about the sources of Elizabethan dramatists it would be better to keep the verb tenses consistent and use adapted and based.
Here’s another example of tense shifting:
The details of Othello’s narrative come from medieval and early modern travel books, some of which described fantastic creatures.
The author uses the present tense for the main text under discussion, but for the other texts—the travel books—switches to the past tense. The switch is understandable: the travel books inspired Othello’s narrative in the past, when the narrative was created. Using the present tense consistently, however, would accurately reflect the status of all the texts mentioned in the sentence as works that exist in the present: The details of Othello’s narrative come from medieval and early modern travel books, some of which describe fantastic creatures.
A word of caution for copyeditors: if an author uses the past or present tense in a consistent manner when discussing works, pause before you follow an impulse to change the tenses, especially if such an intervention would be extensive. The author may have sound reasons for his or her choices, and you would do better to query before you impose one tense over another. If you encounter frequent shifting of tenses for no discernible reason, revising for consistency is a good idea.