Is Banquo's ghost real, or is Macbeth just Hallucinating?
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Is Banquo’s ghost real or a figment of Macbeth’s guilty mind? The uncertainty emphasizes that Macbeth’s fate is part of him, caused by his character: his ambition and guilt.
Macbeth and Lady Macbeth continue to try to lie to keep their secrets and hold on power, but these lies become less and less effective as guilt about the violence they have committed begins to effect them.
Macbeth has become so warped he cannot tell the unnatural from the natural anymore. Lady Macbeth sees lying is useless and chooses isolation: she tells the thanes to leave.
the appirition is nothing but a simple hallucination of a guilty mind