In a soliloquy in the first scene of Act 3, Berowne half-jokingly laments his love for Rosaline. He uses a slew of oxymorons to describe Cupid, the physical embodiment of love:
This wimpled, whining, purblind, wayward boy,
This Signior Junior, giant dwarf, Dan Cupid,
Regent of love rhymes, lord of folded arms,
Th' anointed sovereign of sighs and groans,
Liege of all loiterers and malcontents,
[...]—O my little heart!
Berowne is never without a joke, even when talking to himself. In this scene, he caricatures love as a blind, whining, stubborn child. Love is also presented as a study in contradiction. Cupid is a “Signior Junior,” or an old god who remains a boy forever. He is also a "giant dwarf," small but towering over men. He is the master of poetry (“love rhymes”) as well as the source of sobs and discontent (“folded arms,” “sighs and groans”). The lord finishes by happily complaining about his condition, lamenting, “oh my little heart!”
This passage reflects the play’s difficulty in fundamentally defining love, or even conclusively describing its effect on the men of Navarre. Berowne seems caught halfway between happiness and anxiety throughout the scene, joyful at love’s arrival but uncertain of the future. He deals with this uncertainty through humor. The play, similarly, seems unsure where to come down on the question of love—what it is, how it comes about, whether it has a net positive or negative effect on our lives. The play must content itself with asking this question with a sense of humor, as Berowne does (“What? I love, I sue, I seek a wife?”).
Ferdinand makes fun of Berowne’s interest in Rosaline, describing her as a “star” compared to the “moon” of her mistress, the Princess of France. Berowne responds to the taunt with an oxymoron:
BEROWNE
My eyes are then no eyes, nor I Berowne.
O, but for my love, day would turn to night!
Berowne responds to Ferdinand’s jibe with a seeming contradiction. He says that if what Ferdinand says about the princess and Rosaline is true, then his eyes are not eyes. If Rosaline is so poor compared to the princess, he adds, then he is not Berowne. The lord goes on to reaffirm his commitment to Rosaline and her great beauty in his typical florid language (“O, but for my love..”).
What Berowne means to say with this oxymoron is that if he is wrong about Rosaline's beauty, his eyes are not working as eyes should. In fact, his vision is so clouded, that his eyes shouldn’t even be considered eyes at all. He takes this line of argument a step further, and says that if Rosaline is not the greater beauty, then he is not Berowne. This second half of the line is ironic: obviously, Berowne is Berowne. He means to say that Rosaline’s beauty is as much fact as his very identity, such that the denial of one is as impossible as the denial of the other.
Berowne can always be relied upon for a fancy rhetorical flourish, and his use of oxymoron fits in well with his occasionally baroque style of speaking. Here, the use of this extreme oxymoron reveals something of the intensity of his attraction to Rosaline. The man who was surprised by his own interest in marriage now creates arguments about Rosaline’s beauty with tremendous stakes. The questioning of her worthiness as a love object is presented as tantamount to questioning his own existence and faculties. Berowne certainly has a melodramatic bent, but his passion here is largely genuine.