Explain the importance of the supernatural in Macbeth.
The witches and ghosts which populate Macbeth are of extreme importance to the plot and to the psychology of the main characters. It must be remembered that this play was written during the reign of James I, who believed fervently in witches and witchcraft. The king had even written a book, Daemonologie, which was well-known to the populace, and presumably to Shakespeare. "Whether or not Shakespeare believed in demonic powers, in black and white magic, as King James did, he means the Sisters to be really there, visible to whom they wish and endowed with powers appropriate to demons." (Riverside Shakespeare 1309). Macbeth doesn't even begin to contemplate the murder of Banquo until he hears from the Weird Sisters that he shall be "King hereafter" (I.iii.49-50). Significantly, supernatural forces can predict good things, too (and flatter the king at the same time). When Banquo's ghost is shown in the line of eight Kings, the last king holds a mirror up to the future and shows a long line (of the Stuarts, King James' family line descended from the mythical Banquo) of kings "out to th' crack of doom" (IV.i.117). These, and other supernatural elements, have influence on the plot, and also make predictions about the real world outside of the play. The average playgoer in Shakespeare's time would have been much more likely to believe in the supernatural than people today, so the machinations and temptations of supernatural evil were very powerful to the audience.