Macbeth should not kill Duncan to try and assume position as the King. For one Duncan is Macbeth's cousin. "O worthiest cousin", states that not only that Duncan considers Macbeth worthy, but it's not an unknown fact that they are cousins. There is a difference between being a blood cousin or being a blood but a recognized cousin. The crown is already spoken for anyways, "Our eldest, Malcolm, whom we name here after the Prince …showed first 75 words of 201 total…

…showed last 75 words of 201 total…try and give good advice or thoughts to Macbeth? Their evilness is shown throughout the play a number of times. Act One, scene three "Where hast thou been sister?" "Killing swine." Those lines just prove that they are and care about nothing but there selves. There is no nothing good going to come for Macbeth out of this idea. This is why Macbeth should not try and kill Duncan to assume the position of King.