Prospero is a great magician. He has vast powers. By the exercise of his powers, he can make all the characters in the play behave in any way he likes. Caliban is his slave. He carries out all the orders of Prospero although unwillingly. But he does not disobey Prospero. Prospero treats him as a slave. Ariel is also ever ready to carry out the orders of Prospero. Ariel raises a storm; he brings the. ship ashore to safety ; he sends the sailors to sleep etc. He brings Ferdinand and Miranda closer. He makes the banquet disappear before Alonso and others. He foils the conspiracy of Caliban and of Antonio and Sebastian. He controls the spirits through Ariel. By his supernatural powers, he arranges a masque to entertain Ferdinand and Miranda. The masque is performed by spirits appearing in the disguise of various goddesses like Iris, Juno and Ceres. Prospero also employs certain spirits to trouble Caliban, Stephano and Trinculo with aches and pains. He also makes Alonso feel guilty.
He utilises the services of Ariel to influence the actions of the ship-wrecked passengers. Prospero has also arranged for their arrival in the island by his magic.
Then Prospero allows the characters in the play to act from their own free motives. Ferdinand and Miranda fall in love at first sight of their own free will. It is not due to any supernatural influence. The intrigate of Caliban against Prospero is an act entirely, of Caliban’s own free will, Towards the end of the play, the conscience of Alonso and Gonzalo is aroused.
Summing up, we can say that Prospero wields a powerful influence over the various characters. But he does not treat all his characters as mere puppets. Some of the characters are quite independent. Ferdinand is such a character. He offers Prospero a stiff resistance. Prospsro himself is no tyrant. He does not impose his will on others. Nor does he rob any character of their wills.