In Act II, scene i of Macbeth by Shakespeare, what is significant about what Macbeth says to Banquo about his dream of the Weird Sisters?
Macbeth says, "I think not of them," after Banquo admitts to dreaming about the Weird Sisters (Act II, scene i).
In Act II, Scene 1, Banquo tells Macbeth that he has dreamt of the "three weird sisters" as they have "showed some truth" to Macbeth in calling him Thane of Cawdor. This dream of Banquo's is somewhat ironic since he himself has cautioned Macbeth to not consider what the witches say because
...oftentimes, to win us to our harm,
The instruments of darkness tell us truths (1.3.133-134)
And, now Macbeth, who in the first act has said in an aside,
If chance will have me King, why, chance may crown me,
Without my stir. (1.3.155-156),
denies having thought about the three sisters and their predictions when, in fact, he has dwelt long on what they have said and has even conspired with Lady Macbeth to effect the predictions of the witches. In Act I, also, Macbeth has asked Banquo to speak his mind freely with him when they have had time to think about all that the witches have said, yet now Macbeth dissembles before his friend. This first falsity of Macbeth sets in motion his evil deeds and falsehoods wrought by his "vaulting ambition" and his preoccupations with the influence of the preternatural world.