For such a young person, Juliet exhibits maturity of thought in the first act. When, for instance, her mother asks her if she will consider marrying Paris, the thirteen-year-old Juliet realizes that she is rather young for marriage and bravely expresses reluctance:
I'll look to like, if looking liking move:
But no more deep will I endart mine eye
Than your comment gives strength to make it fly. (1.3.)
Then, after encountering the infatuated Romeo at the masque where he rushes to her as an object of exalted love, Juliet criticizes Romeo's wooing, telling him to act naturally, not poetically. These words indicate Juliet's confidence and sensibility. Further, in Act II, she cautions him not to swear against the moon because it is too inconstant. Then, because she is more mature than Romeo, she warns:
Well, do not swear...
I have no joy of this contract tonight:
It is too rash, too unadvised, too sudden...(2.2)
And yet she pledges her love to Romeo and ends the scene most amorously:
Good night! good night! parting is such sweet sorrow
That I shall say good night till it be tomorrow. (2.2.)
Juliet exhibits fortitude in her willingness to take a potion from Friar Laurence if his plan will enable her to be with Romeo. While she fears the "ancient receptacle," the sepulcher in which she will wait for Romeo, she knows she will wake again, so she steels herself and drinks the potion: "Romeo I come! this do I drink to thee" (4.3).
When she does awaken, it is just minutes too late. She sees the limp body of her love Romeo who, ironically, has given himself to death for her. And, finally, she dies for her love.