This is a common motif in <em>Macbeth</em> that reflects an Elizabethan belief. During Elizabethan times, people had a very weak understanding of mental illness and mental disorders. Moreover, they also equated extreme feelings with insanity. One way in which Shakespeare represents this is through the use of hallucination. This "insane" characteristic can be seen in many of Shakespeare's plays besides <em>Macbeth</em>, such as King Lear in <em>King Lear</em> and Ophelia in <em>Hamlet</em>.
