Quote 4
MACBETH
Is this a dagger which I see before me,
The handle toward my hand? Come, let me clutch thee.
I have thee not, and yet I see thee still.
Art thou not, fatal vision, sensible
To feeling as to sight? or art thou but
A dagger of the mind, a false creation,
Proceeding from the heat-oppressed brain?
I see thee yet, in form as palpable
As this which now I draw.
Thou marshall'st me the way that I was going;
And such an instrument I was to use. (2.1.44-55)
"The dagger made me do it" isn't a defense we've heard before, but it seems to work for Macbeth. Look at that "Come, let me clutch thee": it sounds a lot like he doesn't have a choice.
Quote 5
MACBETH
If't be so,
For Banquo's issue have I filed my mind,
For them the gracious Duncan have I murdered,
Put rancors in the vessel of my peace
Only for them, and mine eternal jewel
Given to the common enemy of man,
To make them kings, the seed of Banquo kings.
Rather than so, come fate into the list,
And champion me to th' utterance! (3.1.69-77)
Well, this is interesting. Here, Macbeth is calling fate to his aid, asking it to "champion" him, or fight for him, in the "lists," or the tournament grounds. This doesn't sound like a fate-or-free-will situation; it sounds like a fate-and-free-will deal.
Quote 6
MACBETH
My thought, whose murder yet is but fantastical,
Shakes so my single state of man
That function is smother'd in surmise,
and nothing is but what is not. (1.3.152-155)
Slow down there, Macbeth, because these ladies haven't said a word about murder. The fact that his first thought is about killing the king is mighty suspicious—almost as though they've just awoken a murderous ambition that's been there all along.