I found out that Macbeth is an equivocator as it says in act 1 scene 7 ‘I have no spur to prick the sides of my intent, but only Vaulting ambition which o’erleaps itself and falls on th’other’ He  explains that he has no confidence to kill Duncan apart from his own ambition to be king. William Shakespeare uses a metaphor and implies that he is saying his intent is a horse by saying ‘I have no spur to prick the sides of my intent.’ The which is in him is his motivation as he cannot spur his horse on