Lord, what fools these mortals be
Puck:
Captain of our fairy band,
Helena is here at hand,
And the youth, mistook by me,
Pleading for a lover's fee.
Shall we their fond pageant see?
Lord, what fools these mortals be!
The mischievous fairy Puck brings his king Oberon to view a spectacle—what he calls a "fond [foolish] pageant." Four Athenian lovers, lost in the fairies' forest, have lately been acting very strangely, and Puck is partly responsible. Where Oberon had hoped to reconcile, with the aid of a love potion, the bickering lovers, Puck applied the potion to the eyelids of the wrong man. Before, Helena had pursued Demetrius, who had pursued Hermia, who was in love with Lysander. Now, because of Puck's mistake, Lysander pursues Helena, and in the meanwhile Oberon has fixed it so that Demetrius pursues Helena too—the result he originally intended.
All this fairy meddling doesn't prevent Puck from blaming the lovers' behavior on their own foolishness. As far as he's concerned, their actions amount merely to a performance put on for the fairies' enjoyment, while the lovers themselves treat the whole affair with deadly seriousness. Shakespeare's judgment seems to be that love is a form of madness that prompts the lover to act in very foolish ways, indeed. As Duke Theseus says, lovers, like madmen and poets, are fantasists, "of imagination all compact [composed]" (Act 5, scene 1, 8). Though their fantasies are irrational, however, they are also acts of creation that produce "More than cool reason ever comprehends" (line 6). Theseus doesn't wholly approve of the frantic delusions of lovers and poets, but the poet Shakespeare is implicitly more tolerant.