act4.sc1. what is the irony of the witches' statement"Something wicked this way comes?.what evidence is there in this scene that macbeth has become...

The irony in the witches' statement lies in their own wickedness. These evil, wicked witches are predicting that "something" is approaching that will bring wickedness as if evil isn't already present in the witches themselves. That "something" turns out to be Macbeth, the first reminder that he has become wicked because of Duncan's murder. 

As the apparitions appear one by one, Macbeth believes that the predictions are reassuring, yet he says he will kill Macduff to make sure that this enemy will not pose a threat. Then Macbeth is very interested to see the fourth apparition to determine if Banquo will have any descendants who will become king, as the witches had predicted for Banquo. Macbeth's horror at the show of eight kings followed by a bloody Banquo shows that he now believes Banquo's prophecy will come true. He will question why he has killed Duncan so that Banquo's children can be king. It appears that more killing will follow as Macbeth demonstrates just how wicked he can become.

Read the scene carefully beginning when the apparitions appear and the witches offer their interpretations. Macbeth's responses reveal his character. Follow the link below.