Quote 4
SEBASTIAN
I remember
You did supplant your brother Prospero.
ANTONIO
True,
And look how well my garments sit upon me,
Much feater than before. My brother's servants
Were then my fellows; now they are my men.
SEBASTIAN
But, for your conscience?
ANTONIO
Ay, sir, where lies that? (2.1.310-317)
Antonio comes easily to his acts of betrayal because he has no conscience, or at the least he represses it well. (Actually, we think he doesn't have one.) Antonio is an example of how one's conscience can get worn out; evil acts become easier and easier with practice.
Quote 5
SEBASTIAN
Sir, you may thank yourself for this great loss,
That would not bless our Europe with your daughter,
But rather lose her to an African,
Where she at least is banished from your eye,
Who hath cause to wet the grief on 't. (2.1.131-135)
Sebastian has no pity, really. It's no wonder he could move so easily from mercilessness to treachery.
Quote 6
ADRIAN
The air breathes upon us here most sweetly.
SEBASTIAN
As if it had lungs and rotten ones.
ANTONIO
Or as 'twere perfumed by a fen.
GONZALO
Here is everything advantageous to life.
ANTONIO
True, save means to live.
SEBASTIAN
Of that there's none, or little.
GONZALO
How lush and lusty the grass looks! How
green!
ANTONIO
The ground indeed is tawny.
SEBASTIAN
With an eye of green in 't.
ANTONIO
He misses not much.
SEBASTIAN
No, he doth but mistake the truth totally. (2.1.49-60)
Reality reflects the nature of the speaker. This is not because reality is false, but because perspective is paramount.