Shakespeare has conceived of and presented Lady Macbeth with extreme care of theatrical technique so that she can play every important part and contribute to the tragic process of the drama. Sometimes some critics tend to compare her activities with witchcraft and call her the “fourth Witch”. But none of these attempts has been successful, as she is very much a flesh and blood character, who exhibits enough of her humanity hidden within in the later scenes. The development of Lady Macbeth’s character acts as a parable with that of Macbeth, thus at once complementing and illuminating the action where necessary.
At the very first appearance of Lady Macbeth, reading a letter from her husband in Act I, scene v, the audience can notice from her facial expressions and eagerness that she is immediately possessed by the prospects of the prophecies. But as she knows the real nature of her husband, she rightly expresses her doubts about the mental strength of her husband, which is necessary to execute so horrible an act as murdering the king. She, however, goes too much in her estimate as she says that her husband’s nature is “too full o’ th’ milk of human kindness”. As a perfect match, therefore, she feels it necessary to,
“Pour my thoughts in thine ear
And chastise with the valour of my tongue.” (Act I, scene v)
Up to this point of the action Lady Macbeth acts as a human being. But as soon as she is informed that the king is coming to her castle, she shows something of the witch-like characteristics in her reactions to the news and in her plotting against the king:
“…come, you spirits
That tend on mortal thoughts, unsex me here,
And fill me, from the crown to the toe, top-full
Of direst cruelty! Make thick my blood;” (Act I, scene v)
What she is wants, is precisely a transformation from a natural human being into something unnatural being, an incarnation of evil, so that she can help her husband in his satanic undertaking. That she wants to devoid herself all the feminine, even maternal qualities—so natural to a woman—is evident from her invitation:
“Come to my woman’s breasts,
And take my milk for gall, you murdering ministers…” (Act I, scene v)
It is from this particular point of reference some critics mark her out as the fourth Witch.
Again, it must be noted that she not only speaks but acts in the satanic fashion when she advises her husband,
“…to beguile the time
Look like the time; bear welcome in your eye,
Your hand, your tongue: look like th’ innocent flower,
But be the serpent under’t.” (Act I, scene v)
This is the narrow Elizabethan version of Machiavellianism, for, true Machiavellianism is directed towards capturing the throne or power at any cost, but of course, for the benefit and welfare of the people. Neither Macbeth nor Lady Macbeth acts with these aims, as the king Duncan was a saint-like figure to his people. This is why Macbeth is seen suffering from terrible mental agony, self-doubt and vacillations. When he is on the verge of breaking down, Lady Macbeth comes to his aid. She even strikes at the softest part of a man’s heart by calling his manhood into question. [She contrasts his weakness of mind with own mental strength, with which she can, she asserts, kill her own sucking baby:
“ I would, while it was smiling in my face,
Have pluck’d my nipple from his boneless gums,
And dash’d the brains out, had I so sworn as you…” (Act I, scene vii)]
Thus she succeeds in dispersing the doubts from his mind and injecting satanic strength necessary for the plot. And when the “deed is done”, when the murder is committed, she instructs him,
“Go get some water
And wash this filthy witness.”
This is perhaps the greatest dramatic irony of any of Shakespeare’s tragedies. From her utterance it is inferred that she takes the matter too lightly—she was ignorant of the consequences arising out of the murder of a king, an act which was considered, according to the Elizabethan ethos, an act against God, a violation of the divine order of the Great Chain of Being created and maintained by God. With this the whole moral universe of the play tumbles down, and accordingly Lady Macbeth gets contracted into her own self.
The grave consequence of the deed is presented scene i, Act V, where the audience learn that Lady Macbeth has fallen victim to a strange kind of disease, that she has become a somnambulist. Here Shakespeare’s conception of her being afflicted with this disease is psychologically plausible. This is purely a psychiatric problem arising her sense of guilt for murdering a saint-like figure in King Duncan. The dramatic irony comes terribly true when she understands her sin and its consequence, guilt:
“Here’s the smell of the blood still: all the perfumes of Arabia will not sweeten this little hand.”
This is a disease, which is now known in psychiatry as obsessive-compulsive disorder.
Lady Macbeth’s suffering is immense and there is no remedy or escape except death. And she dies a tragic death. In this she forecasts the same consequence for Macbeth, and her death weakens him considerably before his final battle. It is also in her tragic death she emerges as a flesh and blood character, a human being, and that is why she cannot be called the fourth Witch. Rather she is that part of the human nature, which aspires, plans, commits misdeeds, reaches the desired point and then terribly falls into the void echoing those words which Macbeth utters upon her death and which anticipates his own impending nemesis:
“Life’s but a walking shadow; a poor player
That struts and frets his hour upon the stage,
And is heard no more.”