From the beginning, we know that the story of Romeo and Juliet will end in tragedy. We also know that their tragic ends will not result from their own personal defects but from fate, which has marked them for sorrow. Emphasizing fate's control over their destinies, the Prologue tells us these "star-cross'd lovers'" relationship is deathmark'd."
In Act I, Scene ii, as Lord Capulet's servant is searching for someone who can read the guest list to him, Benvolio and Romeo enter. Completely by chance, Capulet's servant meets Romeo and Benvolio, wondering if they know how to read. This accidental meeting emphasizes the importance of fate in the play. Romeo claims it is his "fortune" to read — indeed, "fortune" or chance has led Capulet's servant to him — and this scene prepares us for the tragic inevitability of the play.
The lovers will be punished not because of flaws within their personalities but because fate is against them. Ironically, the servant invites Romeo to the Capulet's house, as long as he is not a Montague, to "crush a cup of wine." Only fate could manufacture this unlikely meeting with Capulet's illiterate servant, as only fate will allow Romeo to trespass into the Capulet's domain and meet Juliet.
Love is another important thematic element in the play, which presents various types of love: the sensual, physical love advocated by the Nurse; the Proper or contractual love represented by Paris; and the passionate, romantic love of Romeo and Juliet. How do these various types of love relate to one another? Is physical attraction a necessary component of romantic love? Because words are slippery, Juliet worries that Romeo's protestation of love are merely lies. How can we know if love is true?
Value and Doubleness
Another important theme is the idea of value and doubleness. Just as language is ambiguous, so are value judgments. As the Friar reminds us, "virtue itself turns vice being misapplied, /And vice sometime's by action dignified" (II.iii.17-18). Within a flower, for example lies both poison and medicine. Similarly, the deaths of Romeo and Juliet are tragic but also bring new life to Verona. The Friar's own role in the play contains this ambiguity. Although he tries to help the lovers, his actions lead to their suffering. Shakespeare's message is that nothing is purely good or evil; everything contains elements of both. Ambiguity rules.