"Power poisons every man who covets it for himself" (Chute 126). In the Shakespeare's play, Macbeth, the character, Macbeth, kills the respected King Duncan in his quest for power. However, during his rule, Macbeth demonstrates that he is incapable of mastering the power and responsibilities of being a king. His drive for power and maintaining his power is the source of his downfall. Macbeth is not meant to have authority beyond Thane of Cawdor. When Macbeth is king, he does not use his authority judiciously.
Macbeth's eventual demise is by virtue of his obsession for power and retaining his power. Before he desired the power of being king, Macbeth was a respected noble. He was labeled, "brave Macbeth" (Act I, scene, ii, line 16) for his actions in battle. During a conversation between Duncan and the Captain, the Captain describes how Macbeth brutally slew the rebel Macdonwald:
Disdaining fortune, with his brandished steel,
Which smoked with bloody execution,
... Till he unseamed him from the nave to th' chops,
And fixed his head upon our battlements (act I, scene, ii, lines 17- 23).
In his speech, the Captain describes Macbeth's violence to indicate what a good warrior he is thus showing that he has respect for Macbeth. Once Macbeth became king, he became overpowered with keeping his authority. Macbeth realized that he was being used just so that Banquo's sons can inherit the throne:
They hailed him father to a line of kings.
Upon my head they placed a fruitless crown,
And put a barren sceptre in my gripe,
Thence to be wrenched with an unlineal hand,
No son of mine succeeding (act III, scene 1, lines 60-64).
Macbeth feeling this way convinces a pair of men to kill Banquo and his son Fleance. By having Banquo and Fleance murdered, Macbeth believes that it will prevent Banquo's sons from becoming king. Macbeth also hires the murderers to kill Macduff's family. This demonstrates Macbeth's obsession because it indicates that Macbeth values his power over his friends. His obsession with power causes Macbeth to feel guilty and lose his sanity. Macbeth's guilt and loss of sanity is indicated in the hallucinations he experiences. His first hallucination occurs just before killing King Duncan. Macbeth sees "A dagger of the mind, a false creation" (act II, scene I, line 38).