Macbeth: Ambition is Root of All Evil It is said that ambition is the key to success. In the case of Shakespeare's Macbeth, it is the key to his downfall. He is presented with the ambition by the supernatural power of the witches. Lady Macbeth, his wife, then pushes the ambition. After the murdering of Duncan, Macbeth has gained enough ambition himself to cause his own destruction. We can see a clear building of desire throughout the play. Macbeth is first introduced to the limits of his power and his ambitions by the witches, who greet him with three titles: Thane of Glamis, which Macbeth is fully aware of; Thane of Cawdor, which is true at