Quote 1
ALONSO
O, it is monstrous, monstrous!
Methought the billows spoke and told me of it;
The winds did sing it to me, and the thunder,
That deep and dreadful organ pipe, pronounced
The name of Prosper. It did bass my trespass.
Therefore my son i' th' ooze is bedded, and
I'll seek him deeper than e'er plummet sounded,
And with him there lie mudded. He exits
SEBASTIAN
But one fiend at a time,
I'll fight their legions o'er.
ANTONIO
I'll be thy second. (3.3.116-126)
Alonso is willing to face his treachery against Prospero, even though it horrifies him. Sebastian and Antonio will not, though. Is this because they're strong, stubborn, or completely removed from their own personal accountability?
Quote 2
ALONSO
Whe'er thou be'st he or no,
Or some enchanted trifle to abuse me
(As late I have been) I not know. Thy pulse
Beats as of flesh and blood; and since I saw thee,
Th' affliction of my mind amends, with which
I fear a madness held me. This must crave,
An if this be at all, a most strange story.
Thy dukedom I resign, and do entreat
Thou pardon me my wrongs. But how should
Prospero
Be living and be here? (5.1.123-133)
Alonso didn't have a strong sense of reality to begin with—he knows he is easily swayed by flattering words, and he now realizes he can no more trust his eyes than his easily influenced intuitions.
Quote 3
ALONSO
If this prove
A vision of the Island, one dear son
Shall I twice lose.
SEBASTIAN
A most high miracle! (5.1.205-208)
Sebastian, seeing that the Prince lives, realizes that his view of reality was swayed by Antonio's evil persuasion; he lets go of the idea of usurpation as easily as he came by it.