What is significant about this quote spoken by Romeo in Act 1, Scene 2 of Shakespeare's Romeo and Juliet, "One fairer than my love? The all-seeing sun/ Ne'er saw her match since the first world begun" (I.i.96-97)?
In Act 1, Scene 2, after Paris and Lord Capulet have their conversation in which Paris tries to convince Capulet, once again, to allow him to marry Juliet, Benvolio tries to convince Romeo to consider other women than Rosaline. Lord Capulet invites Paris to court his daughter at a ball Capulet is giving that night; Benvolio and Romeo hear about the ball, and knowing that Rosaline, as a relation of Capulet's, will be there as well, Benvolio thinks it is the perfect moment for Romeo to gain a better perspective on his alleged love for Rosaline. He urges Romeo to crash the ball with him because Rosaline will be there surrounded by all the other beauties of Verona. Benvolio feels that if Romeo can compare Rosaline to other beautiful women, he'll soon give up his obsession with Rosaline, seeing that other women are far more beautiful than she is.
The lines in question are Romeo's response to Benvolio's attempt at persuading him. Romeo feels it would be sacrilegious for him to begin worshiping another woman than Rosaline. He also feels that he couldn't possibly think that another woman is more beautiful than Rosaline. When Romeo asks Benvolio, "One fairer than my love?," he is asking this with an incredulous tone, meaning that he completely disbelieves in the truth of Benvolio's idea (I.ii.96). Romeo can't possibly believe that he could see someone as being more beautiful than Rosaline. In his next line, "The all-seeing sun / Ne'er saw her match since first the world begun," Romeo is comparing Rosaline to the sun (96-97. He is referring to the sun as "all-seeing" because it lives in the sky, looking down on all the world, seeing all. He is further saying that nothing is more beautiful than the sun, and Rosaline is like the sun; therefore, no one is more beautiful than she is.
The significance in Romeo's lines is that they are actually quite ironic. The lines represent a perfect example of dramatic irony. Dramatic irony is a moment in which the character's own limited understanding contrasts with the action of the plot, plus the audience's own understanding. The audience has already been given a clue from the Prologue that Romeo falls in love with someone else; therefore, the audience can guess that Romeo is speaking wrongly here. The audience can already predict that Romeo will soon eat his words here and soon forget all about Rosaline as a woman who can barely compare with Juliet.