In Macbeth, the witches' prophecies inspire Macbeth to pursue power, leading him to commit heinous acts and eventually descend into madness and self-destruction. Their role in the play is pivotal, as they manipulate Macbeth's ambitions and exploit his weaknesses, pushing him towards his tragic fate.
Iago, on the other hand, operates through cunning, manipulation, and deceit. He plants seeds of doubt and jealousy in Othello's mind, leading to Othello's downfall and destruction of his relationship with Desdemona. Iago's actions serve as the driving force behind the play's tragic events, making him a central figure in the plot.
Moreover, both the witches and Iago take on roles that enhance their impact as catalysts. The witches appear as supernatural entities, instilling a sense of otherworldly malevolence and influencing Macbeth's actions through prophecies and visions. Iago, on the other hand, is a Machiavellian schemer who works behind the scenes, using his charisma and cunning to orchestrate Othello's downfall.
Therefore, the witches and Iago play crucial roles as catalysts in their respective plays, shaping the course of events and the subsequent tragedies that befall Macbeth and Othello.