A Trail of Death and Supernatural Chaos
The weird sisters might not wield the daggers themselves, but they're responsible for every major death in the play. Duncan dies because they convince Macbeth he's destined to be king. Banquo dies because his prophecy about getting kings threatens Macbeth's paranoid mind.
Sleep deprivation becomes a recurring motif after the witches appear. Both Macbeth and Banquo struggle with sleeplessness after their encounter. Macbeth's so exhausted he hallucinates the famous dagger, and later hears voices saying "Macbeth does murder sleep." This constant tiredness feeds his paranoia and poor decision-making.
The supernatural elements throughout the play all trace back to the witches' influence. Lady Macbeth calls on dark spirits to "unsex me here" - likely the same supernatural forces. Banquo's ghost, the apparitions, even Lady Macbeth's final descent into madness all stem from that initial encounter with the weird sisters.
Remember: The witches don't just predict fate - they actively reshape it by exploiting human weaknesses like ambition and fear.
The essay convincingly argues that without the witches' manipulation, none of the tragedy would have occurred. They're the true architects of Macbeth's downfall.