You are intrigued as you overhear Ferdinand speaking about this woman that he's going to marry. Enter Prospero's daughter. Ferdinand asks her name (she promised her father that she wouldn't give her name to Ferdinand)....she gives her name to him. So, at this point, if you are Prospero..you are upset that she's disobeyed you. He continues to listen to them declare their undying love for each other...at which point, you change your mind and decide it's not a bad thing after all.
