| Quote #4
Here's another count against ambition: After reading the letter from her husband (which recounts the witches' prophesy), Lady Macbeth's thoughts immediately turn to murder. Problem: Macbeth has ambition, but he doesn’t have the nerve to see it through. Luckily Lady Macbeth is man enough for both of them.
| Quote #5
MACBETH […] I have no spur To prick the sides of my intent, but only Vaulting ambition, which o'erleaps itself And falls on the other. (1.7.1)
Time to be real: when Macbeth is honest with himself, he admits that there's no good reason to kill Duncan, because Duncan is perfectly good at this whole king-business. Macbeth just wants that power for himself.
| Quote #6
ROSS 'Gainst nature still! Thriftless ambition, that wilt ravin up Thine own life's means! Then 'tis most like The sovereignty will fall upon Macbeth. (2.4.6)
Ross is right about one thing: ambition is to blame for Duncan's murder. He's wrong about the most important part, though. Here, he accuses Duncan's kids of going "'gainst nature" and killing their own father—but Macbeth is the one to watch out for. Our question: is Macbeth going against nature, too, by killing the king? Is ambition of any kind unnatural?