Macbeth, although largely responsible, was not totally responsible for the torrent of evil which was unleashed in Scotland after after Duncan's death. Both Lady Macbeth and the supernatural powers must accept at last some of the responsibility for the evil deeds unleashed during Macbeth reign. They both forced Macbeth to be proactive in chasing the crown at a time when he was of the opinion that
" If chance may have me king why chance may crown me."
The play began with the forces of evil stirring Macbeths ambitions nature by declaring that he " shall b king thereafter." They then said of thou be none." Banquo noted how Macbeth looked fearful and he must have realised the witches put into words what Macbeth had been thinking. The supernatural forces not only got Macbeth thinking about how he could become king but also laid the foundations for his feelings of insecurity that would lead to his subsequent murder of Banquo.
The major external influence pushing Macbeth to kill Duncan was Lady Macbeth. She knew her husband was " too full o' the milk of human kindness" to take the initiative and she resolved to push him into murdering Duncan Macbeth was so upset after killing Duncan he stated " I'll go no more,
I am afraid to think what I have done". Lady Macbeth then accepted the responsibility of taking the daggers and smearing the grooms with blood. She had goaded Macbeth into killing Duncan and she stopped him from falling apart with remorse after having done the deed.
Macbeths reign as king was one of fear and insecurity that others would take the crown from him. Of Banquo he said " their is none but he whose being I do fear". Macbeth was obviously thinking back to the prophesies of the witches and he resolved to kill Banquo. After killing Banquo, Macbeth stated" I am in blood stepped in so that, should I invade no more returning were tedious as go o'er". Macbeth has reached the stage that he feels he has done so many evil deeds that he must keep going.
Macbeth begins to become unstable after killing Banquo and he keeps seeing Banquo's ghost appear before him at the banquet.
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