The budding relationship between Ferdinand and Miranda is one of the most important but also unlikely aspects of the play's plot. The contradictory role of her very manipulative father is evident here, as Prospero congratulates himself that things are turning out just as he planned. Prospero's hypocrisy and self-centered lack of real regard for others are also on display. He lurks and spies on the young people and brags that he has engaged in all his unethical dealings just for his daughter's benefit rather than his own.
When the young people meet, they are very confused. Ferdinand is literally lost: shipwrecked, he has no idea where he is. Miranda has memories only of the island and the people she knows there. Ferdinand is the first possible peer, as a potential friend or romantic partner, she has ever met. Shakespeare leans on the dramatic convention of true love as destiny to make their unlikely sudden affinity believable. It is fate rather than her father's magic that brings them together. This distinction is important because if their union had resulted from his sorcery, it would be a false basis for all the further plot developments, which lead to the restoration of his right to rule and Miranda's legacy.
In act 3, scene 1 of William Shakespeare's The Tempest, Prospero watches unobserved from a distance while Ferdinand and Miranda profess their love for one another and resolve to be married—just as Prospero hoped they would.
Prospero says that everything he does is for Miranda's benefit.
PROSPERO: I have done nothing but in care of thee. (1.2.19)
For the most part, this is true. Prospero brought Ferdinand and Miranda together so they would fall in love and Miranda would be happy, but Prospero also has ulterior motives. He hopes that the marriage of his daughter to Ferdinand, the son of Alonzo, the King of Naples, will help restore Prospero to his former position as Duke of Milan.
This is all part of Prospero's larger plan to take revenge on those who usurped his dukedom and cast him adrift with three-year-old Miranda twelve years ago.
However, Ferdinand and Miranda's inherent goodness and their caring relationship demonstrates the kindness and humanity of one person towards another, and this tempers Prospero's desire for revenge against the people who wronged him.
Prospero confronts his brother, Antonio, for usurping his dukedom, and he criticizes Alonzo for assisting Antonio in his usurpation. Due to Ferdinand and Miranda's positive influence on him, however, Prospero forgives Antonio and Alonzo and restores their ship so that everyone can sail back to Naples for Ferdinand and Miranda's wedding.
This scene, which features the main courtship of Ferdinand and Miranda, raises many interesting issues that are central to the play as a whole. One of the crucial things it is important to remember is the role of Prospero in this scene. Even though the main action of the scene only concerns his daughter and his future son-in-law, Prospero, as always, is present, cloaked in invisibility, as he stagemanages what occurs on his island and ensures that his will becomes reality. This is a central theme of the play, as Prospero is a figure who is shown to have immense authority and power on his island as he uses his own magic and his control of Ariel to effectively divide the different groups and supervise them, bringing them together according to his will and enacting a resolution as he desires in his timing. Note Prospero's words at the very end of this scene:
So glad of this as they I cannot be,
Who are suprised with all; but my rejoicing
At nothing can be more.
Prospero says that although he cannot share in Ferdinand and Miranda's gladness because it comes from surprise, he is definitely able to rejoice with them. He is not surprised because the union of his daughter and Ferdinand is something he has planned. His total control of the island allows him to bring this plan to fruition, and his invisible presence in this scene is symbolic of his control of the entire island and the action of the play. That this scene concerns the romantic engagement of two characters only serves to emphasise the theme of Prospero's control: their love has been planned and Prospero is the director of this scene, watching his plan develop and become reality.