Our revels now are ended. These our actors,
As I foretold you, were all spirits, and
Are melted into air, into thin air;
And, like the baseless fabric of this vision,
The cloud-capped towers, the gorgeous palaces,
The solemn temples, the great globe itself,
Yea, all which it inherit, shall dissolve;
And, like this insubstantial pageant faded,
Leave not a rack behind. We are such stuff
As dreams are made on, and our little life
Is rounded with a sleep. (IV.i.148–158)

Prospero speaks these lines just after he remembers the plot against his life and sends the wedding masque away in order to deal with that plot. The sadness in the tone of the speech seems to be related to Prospero’s surprising forgetfulness at this crucial moment in the play: he is so swept up in his own visions, in the power of his own magic, that for a moment he forgets the business of real life. From this point on, Prospero talks repeatedly of the “end” of his “labours” (IV.i.260), and of breaking his staff and drowning his magic book (V.i.54–57). One of Prospero’s goals in bringing his former enemies to the island seems to be to extricate himself from a position of near absolute power, where the concerns of real life have not affected him. He looks forward to returning to Milan, where “every third thought shall be my grave” (V.i.315). In addition, it is with a sense of relief that he announces in the epilogue that he has given up his magic powers. Prospero’s speech in Act IV, scene i emphasizes both the beauty of the world he has created for himself and the sadness of the fact that this world is in many ways meaningless because it is a kind of dream completely removed from anything substantial.

His mention of the “great globe,” which to an audience in 1611 would certainly suggest the Globe Theatre, calls attention to Prospero’s theatricality—to the way in which he controls events like a director or a playwright. The word “rack,” which literally means “a wisp of smoke” is probably a pun on the “wrack,” or shipwreck, with which the play began. These puns conflate the theatre and Prospero’s island. When Prospero gives up his magic, the play will end, and the audience, like Prospero, will return to real life. No trace of the magical island will be left behind, not even of the shipwreck, for even the shipwreck was only an illusion.