Quote 7
BRABANTIO
Look to her, Moor, if thou hast eyes to see.
She has deceived her father, and may thee. (1.3.333-334)
Brabantio suggests that, because Desdemona deceived her father when she eloped with Othello, Desdemona will likely deceive her husband. Desdemona, as we know, is completely faithful to Othello. The problem is that Othello seems to buy into the stereotype that unruly daughters make for unruly and promiscuous wives, which is part of the reason why Iago is able to manipulate him so easily. (Later, in Act 3, Scene 3, when Iago echoes Brabantio's point, Othello agrees.) Shakespeare seems to be critiquing this unfair attitude toward women in the play – Othello's distrust in his wife leads to a terrible tragedy when he murders Desdemona.
Quote 8
BRABANTIO
It is too true an evil. Gone she is,
And what's to come of my despisèd time
Is nought but bitterness.—Now, Roderigo,
Where didst thou see her?—O, unhappy girl!—
With the Moor, say'st thou?—Who would be a
father?—
How didst thou know 'twas she?—O she deceives
me
Past thought!—What said she to you?—Get more
tapers.
Raise all my kindred.—Are they married, think
you?
[…]
O heaven! How got she out? O treason of the blood!
Fathers, from hence trust not your daughters' minds
By what you see them act. (1.1.178-189; 191-193)
When Brabantio learns that Desdemona has run off with Othello, he cries out, "Who would be a father!" and wonders "what's to come" of himself. Clearly, Brabantio feels as though his identity as a father and an authority figure have been compromised by Desdemona's elopement, which he interprets as "treason of the blood."
Quote 9
BRABANTIO
A maiden never bold,
Of spirit so still and quiet that her motion
Blushed at herself. And she, in spite of nature,
Of years, of country, credit, everything,
To fall in love with what she feared to look on!
It is a judgment maimed and most imperfect
That will confess perfection so could err
Against all rules of nature, and must be driven
To find out practices of cunning hell
Why this should be. I therefore vouch again
That with some mixtures powerful o'er the blood,
Or with some dram conjured to this effect,
He wrought upon her. (1.3.112-124)
Brabantio doesn't seem to know his daughter at all, especially when he claims she is "never bold" and that she "fear'd to look on" Othello. As we know, Desdemona is bold – she runs off with a man her father doesn't approve of and defends her actions when confronted by Brabantio and the Venetian court.