Final answer:
Banquo's cautious skepticism contrasts with Macbeth's concealed ambition and curiosity following the witches' prophecy. While Banquo remains level-headed, Macbeth reveals a readiness for the fulfillment of the prophecies through his asides, indicating a growing desire for power.
Step-by-step explanation:
The contrast between Banquo's and Macbeth's reactions to the witches' prophecy showcases different levels of ambition and credulity. When the witches hail Macbeth as the Thane of Glamis, Thane of Cawdor, and the future king, Macbeth's reaction is one of disbelief and curiosity, but also latent ambition. He questions the witches, desiring to know more, indicating his intrigue and underlying desire for power. As the prophecy begins to come true with Macbeth's new title as Thane of Cawdor, his ambition starts to surface, suggested by his aside that ‘If chance will have me, king, why, chance may crown me, Without my stir.’ In contrast, Banquo remains skeptical of the witches and their prophecy. Even when it is clear that part of the prophecy has been fulfilled, Banquo retains his composure and does not seem to be seduced by the power or titles that might be inferred from the prophecy. Macbeth's ambition is further revealed in his aside ‘Come what come may, Time and the hour runs through the roughest day,’ expressing a willingness to let events unfold that may lead him to kingship. Banquo's reaction is more measured and cautious compared to Macbeth who harbors an inner ambition, which is sparked by the prophecy and gradually consumes him.