Final answer:
Macbeth's downfall in Shakespeare's play is often attributed to his own ambition. Still, it's arguable that Lady Macbeth's overarching ambition and manipulation significantly contribute to the tragic events, making her ambition a potential hamartia.
Step-by-step explanation:
Many readers and critics of Shakespeare's Macbeth consider the protagonist's ambition to be his hamartia, leading to his downfall. However, a strong case can be made that it is actually Lady Macbeth's ambition that serves as the true catalyst for tragedy. In the text, it is she who ignites Macbeth's desire for power with her manipulation and taunting. When Macbeth hesitates to murder King Duncan, Lady Macbeth questions his manhood and aggressively convinces him to proceed with their plan. This determination and influence from Lady Macbeth suggest that she plants the seed of ambition in Macbeth, pushing him toward actions that he may not have taken on his own.
Lady Macbeth's ambition is evident from her soliloquy in Act 1, Scene 5, where she calls on the spirits to 'unsex' her, fill her with cruelty, and rid her of feminine weakness. She becomes the mastermind behind the plot to kill King Duncan, displaying an ambition not only for herself but mainly for Macbeth, whom she desires to see as king. Her overpowering presence and relentless persuasion play a critical role in Macbeth's decision-making process. The tragedy of Macbeth, therefore, can be viewed through the lens of Lady Macbeth's ambitions which serves as the impetus for the play's tragic events.