Mercutio, the witty skeptic, is a foil for Romeo, the young Petrarchan lover. Mercutio mocks Romeo's vision of love and the poetic devices he uses to express his emotions:
Romeo, Humors! Madman! Passion! Lover!
Appear thou in the likeness of a sigh,
Speak but one rhyme and I am satisfied.
(II.1.7–9)
Mercutio is an anti-romantic character who, like Juliet's Nurse, regards love as an exclusively physical pursuit. He advocates an adversarial concept of love that contrasts sharply with Romeo's idealized notion of romantic union. In Act I, Scene 4, when Romeo describes his love for Rosaline using the image of love as a rose with thorns, Mercutio mocks this conventional device by punning bawdily:
If love be rough with you, be rough with love;
Prick love for pricking and you beat love down.
(I.4.27–28)
The Queen Mab speech in Act I, Scene 4, displays Mercutio's eloquence and vivid imagination, while illustrating his cynical side. Mercutio, unlike Romeo, doesn't believe that dreams can act as portents. Fairies predominate in the dream world Mercutio presents, and dreams are merely the result of the anxieties and desires of those who sleep.
Mercutio's speech, while building tension for Romeo's first meeting with Juliet at the Capulet ball, indicates that although Mercutio is Romeo's friend, he can never be his confidant. As the play progresses, Mercutio remains unaware of Romeo's love and subsequent marriage to Juliet.
