Although included in the comedy section of the First Folio, Measure for Measure has been called tragedy, tragicomedy, satire, and allegory by its critics. Scholars have argued that the play is a comedy only by the force of the contrived happy ending. Its theme, characters, and action are tragic, and only the manipulations of the duke, who acts as a deus ex machina, bring the play to a happy conclusion. The eloquent poetic passages on the ephemerality of life and the fear of death's unknown realm are cited as indications of the tragic style.
The play has been related to Shakespeare's personal life. The poet is said to have been immersed in a tragic vein at the time Measure for Measure was written. He was in the midst of the creative flow which produced his great tragedies: Hamlet, Othello, King Lear, and Macbeth. A "sex nausea" is said to have overcome him at this period. Scholars have seen the evidence of collaboration in the play as implication that Shakespeare's devotion to the play was half-hearted, that he had no stomach for comedy at this time of his life. Biographical evidence is slight, however, and theories are based mainly upon the content of the plays and sonnets. It is only speculation to assume that the play suffered from its author's depression, sex revulsion, or tragic mood.
In considering what genre the play exemplifies, it is well to note that comedy in Shakespeare's time was chiefly identified by its happy ending. Conventions of romantic comedy of the seventeenth century included an idealized heroine, love as the basic theme, and a problem brought to happy conclusion. Tragicomedy offered a tragic theme with a happy close brought about by the intervention of a deus ex machina. Conventions included characters of noble rank, love as the central theme (its ideal forms contrasted with the vulgar), disguise, and virtue and vice thrown into sharp contrast. Clearly, Measure for Measure might fall into either category and may reasonably be considered both romantic comedy and tragicomedy.
Numerous modern critics have objected to the abrupt appearance of a happy ending, but the reader should keep in mind that this was a convention of romantic comedy with which Shakespeare's audience was well acquainted.