Why does Olivia fall in love with Viola and not Orsino? Using Act 1 Scene 1 and Act 1 Scene 5.
One of the chief complaints against the character of Duke Orsino is that he is more in love with the melancholy feeling of being in love than with Lady Viola herself. This is made clear from the very first speech of the play:
If music be the food of love, play on;
Give me excess of it, that, surfeiting,
The appetite may sicken, and so die.
Orsino is in a lover's mood but it is clear he likes being in this state. Even when Curio tries to distract him by getting him to go hunting, Orsino, love-sick as he is, can only pun cleverly by associating the hart with the object of his affections. It is interesting that he himself will not go to testify his love for Lady Olivia - he always sends messengers to testify his love, perhaps another indication that he likes this state of love-wrought excitement and almost does not want it to end.
In Act I Scene 5 we see Viola as Caesario delivering Orsino's speech. It is interesting that she does this in a way that makes Orsino's love treaties to be absurd. She starts off in a rather hackneyed fashion; "Most radiant, exquisite and unmatchable beauty" (hardly original), before stopping to verify who the lady of the house is. She also makes pains to stress the artificiality of her speech, which undercuts its persuasive power:
Most radiant, exquisite and unmatchable beauty,--I
pray you, tell me if this be the lady of the house,
for I never saw her: I would be loath to cast away
my speech, for besides that it is excellently well
penned, I have taken great pains to con it. Good
beauties, let me sustain no scorn; I am very
comptible, even to the least sinister usage.
Later, Caesario says again, "Alas, I took great pains to study it, and 'tis poetical". Viola immediately picks up on this in her response: "It is the more like to be feigned. I pray you, / keep it in." However, it is when Caesario says how he (she) would woo Olivia that Olivia is attracted to him - when she speaks her own original and non-practiced words, in one of the most romantic speeches of the play:
Make me a willow cabin at your gate,
And call upon my soul within the house;
Write loyal cantons of contemned love
And sing them loud even in the dead of night;
Halloo your name to the reverberate hills
And make the babbling gossip of the air
Cry out 'Olivia!' O, You should not rest
Between the elements of air and earth,
But you should pity me!
This unpracticed speech is from the heart, and infinitely more attractive than Orsino's studied and impersonal declarations of love.
It is a common theme in Shakespeare's comedies to find a character falling in love with another, not knowing the attraction is actually a homosexual one. This would have been particularly amusing to the contemporary audience because, of course, all the characters were played by men, adding an increased level to the gender-bending and confusion.
In Twelfth Night, the character of Orsino is a farcical one, speaking words the audience would have recognized as typical of the unoriginal courtly love sonnets of the time. Orsino craves love but is not constant, stating that his feelings of love fall "into abatement and low price / Even in a minute." His declaration that Olivia seems able to "purge the air of pestilence" is romantic hyperbole. Evidently, he does not know her as a human being but only thinks of her as a romantic goal to be attained.
By contrast, Viola, when she enters as a messenger in act 1, scene 5, parries verbally with Olivia and attracts her attention from the beginning—Olivia jokes with her, "Are you a comedian?" as she introduces Orsino's overblown words. Viola asks to see Olivia's face and praises it honestly—"Excellently done, if God did all." When Olivia declares that she cannot love Orsino, Viola declares herself to be "a gentleman" and describes how she herself would not anticipate a denial from Olivia, if she loved her—instead, she would "write loyal cantons of contemned love."
Accordingly, Olivia says she cannot love Orsino unless he sends Viola again "to tell me how he takes it." Effectively, Olivia is far more attracted to Viola because she sees in her someone more honest, direct, and genuine—itself a dramatic irony, because the audience knows Viola to be a woman disguised as someone else.