It is the time when people who are sleeping have nightmares.
He alludes the fact that without Nature in a right state of mind, evil threatens sleep.
During the night before Banquo’s murder Macbeth meets with murders in a dark area within his castle.
They speak of killing, which in all senses is evil.
In his analysis of the images of darkness in Macbeth, Shakespearean scholar A.
C Bradley writes: "It is remarkable that almost all the scenes which at once recur to memory take place either at night or in some dark spot.( Shakespeare,1994; 29) Witches do not directly advice Macbeth to kill King Duncan, they use a subtle form of temptation when they inform Macbeth that he is destined to be king, by placing this thought in his mind, they guide him on the path to his own destruction.Banquo foreshadows the terrible events to come with an allusion to the witches as " instruments of darkness" that sometimes speak the truth in order to bring their listeners to ruin.The murders that are seen occur during the night which makes us realize that the darkness has influence on characters.This tragedy is full of the examples that describe the use of night and dark imagery to show the darker side of humans.The vision of the dagger, the murder of Duncan, the murder of Banquo, the sleep-walking of Lady Macbeth, all come in night-scenes.The Witches dance in the thick air of a storm, or, 'black and midnight hags,' receive Macbeth in a cavern.During the conversation between Macbeth and Lady Macbeth after the Duncan’s murder Lady Macbeth makes mention of "the owl that shriek’d and the crickets’ cry".( Shakespeare, 1994; 46) "The owl clamours all through the night; Duncan's horses devour each other in frenzy; the dawn comes, but no light with it.Common sights and sounds, the crying of crickets, the croak of the raven, the light thickening after sunset, the homecoming of the rooks, are all ominous".( Bradley, 1905;337).The disorder in Nature is symbolized by the slaying of the falcon, the royal bird, by an owl.Darkness is used to illustrate the unnatural character of Macbeth’s crime in killing the king which was considered at that time to be crime against God and nature.