The start of events that contribute to Macbeth’s delusions are when he is right outside of King Duncan’s room. Before Macbeth enters, he begins to hallucinate and thinks that he sees a dagger before him with the end pointing toward him, and the tip pointing towards Duncan. Macbeth tries to grasp the weapon and fails. He wonders whether what he sees is real or a “dagger of the mind, a false creation, proceeding from the heat-oppressed brain” (Macbeth). Macbeth, trying to rationalize his coming murder of King Duncan, continues his great "If it were done" (Macbeth) soliloquy. Unfortunately, as Macbeth has just explained to himself, there's no real justification for the crime. Duncan is a guest in his home, and also a great king. Therefore, Macbeth has no "spur" to act upon his ideas, which is compared to a wild horse. Continuing the horse metaphor, he can only draw on his desire for powe. His desire vaults even beyond its natural limits to land on "th'other" (the other side) probably, to land somewhere unknown and beyond reason. This figment of his imagination is the beginning of crimes yet to occur. The dagger suggests that the act he is about to commit is getting to him already. Macbeth’s vision establishes his guilt. The dagger scene highlights Macbeth’s own awareness of his ambition. As he says, his “vaulting ambition”(Macbeth) takes over all of his other thoughts and emotions that he feels, and shows his great desire for power. Macbeth’s behavior can be judged reasonable because if it hadn’t been for the witches who put the idea of him becoming King in his head in the first place, and the persuasion of Lady Macbeth to kill the king, Macbeth wouldn’t have thought twice about becoming King.
The next event that contributes to Macbeth’s delusion is the killing of Banquo. With Macbeth worried that the witch’s prophecies might come true for Banquo, Macbeth hires two murders to kill Banquo and his son Fleance. Remember, also, that with Duncan’s murder, Macbeth’s guilty conscience is already manifesting itself in the form of many sleepless nights. Macbeth tells his wife that he has planned “a deed of dreadful note” (Macbeth) for Banquo and Fleance and urges her to be cordial and kind to Banquo during the evening’s feast, in order to draw their next victim into a false sense of security. It is dusk, and the two murderers hang around in a wooded park outside the palace. Banquo and Fleance approach on their horses and get off. They light a torch, and the murderers set upon them. The murderers kill Banquo, who dies urging his son to flee and to avenge his death. One of the murderers puts out the torch, and in the darkness Fleance escapes. The murderers leave with Banquo’s body to find Macbeth and tell him what has happened. The news of Fleance’s escape angers Macbeth. If only Fleance had died, he ponders, his throne would have been safe. Instead, “the worm that’s fled/Hath nature that in time will venom breed” (Macbeth). With Fleance still alive, it weighs heavy on Macbeth’s mind. Fleance is just a boy now, but he could grow up and one day avenge the death of his father’s murder, and take over the throne. Macbeth’s position is not secure, and he is feeling a lot of anxiety over it. Returning to his guests, Macbeth goes to sit at the head of the royal table but finds Banquo’s ghost sitting in his chair. Dismayed, Macbeth speaks to the ghost, which is invisible to the rest of the company. Lady Macbeth makes excuses for her husband, saying that he occasionally has “visions” (Macbeth) and that the guests should simply ignore his behavior. Although Macbeth didn’t kill Banquo himself, Banquo’s blood is still on Macbeth’s hands, causing him to go delusional. With the sight of Macbeth seeing the ghost of Banquo, we can officially say that Macbeth is delusional Macbeth’s behavior can be judged reasonable because if he had not killed Banquo, he would have risked giving up the crown, which he has worked so hard to achieve. Macbeth’s greed for the throne get’s in the way of his sanity, just like the character Kurtz from Joseph Conrad’s Heart of Darkness, whose demanding hunger for ivory drove him from his sanity and made enemies among the native Africans. Same with Macbeth, whose desire for power drove him to make enemies amongst most of Scotland.
