Macbeth defines his moral baseline when he protests murdering Duncan. He is confused by the witches’ first prophecy, and then worried as to how it would come true. He expresses his horror at the very idea of killing King Duncan, saying
“why do I yield to that suggestion
Whose horrid image doth unfix my hair
And make my seated heart knock at my ribs,
Against the use of nature?”(I, iii, lines 144-147) and he hopes that fate will take care of the prophecy without his help. Later Macbeth paces, considering all the reasons why he shouldn’t kill Duncan. Macbeth is thankful that Duncan has just made him Thane of Cawdor. He believes it his duty to protect Duncan, and that Duncan has been a fair leader. He acknowledges that only his ambition pushes him to kill …show more content…
After Macbeth rules his morals more strong than his ambition, Lady Macbeth enters to ensure Macbeth kills Duncan. To mount his ambition, she insults his manhood and assures him that if he has courage, all will go well. She tells Macbeth, “screw your courage to the sticking-place, / And we’ll not fail”(I, vii, lines 67-68) when he doubts their success. Lady Macbeth’s desire to be Queen of Scotland is what sparks Macbeth's own desire to be King of Scotland. Macbeth’s ambition then overpowers his morals and he kills Duncan. This is a huge shift in his value of human life, as before he was horrified at the very thought of killing his