Sleep imagery is representative of the paranoia and psychological anguish that one is consumed by when they seek to gain power through unethical means. In MacBeth, imagery of sleep or more so “lack of sleep” imagery is important as we see this insomnia as a psychological impact of committing an evil act for one’s own gain.
We see MacBeth’s initial paranoia in Act 2 Scene 1 when he comes across the floating image of the dagger before he enters Duncan’s chamber and in his soliloquy says: “Thus to mine eyes. Now o'er the one half-world Nature seems dead, and wicked dreams abuse The curtained sleep.” MacBeth refers to “wicked dreams” or nightmares that plague those who are alive The audience Act 2, Scene 2, immediately after his immoral murder