It would be easy to blame the entire disruption of the balance of good and evil on the supernatural powers of the three witches, but the true cause of the evil comes from the moral decisions of men.
Macbeth was not born evil. At the start of the play Macbeth was a worthy and honorable man. The moment he hears the prophecies of the three witches, he begins his journey towards evil. Even while he is plotting to kill Duncan, he still shows signs of goodness and sanity in him. It took the little nudge he gets from his wife, Lady Macbeth, to finally complete his transformation into an evil man. There are little signs in this play of any man who is somewhere in between the sides of good and evil, except for the short period in which Macbeth is contemplating whether or not he should go through with the murder of Duncan. As Goddard states.
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Men are neither good nor evil. In Nature the good and the bad,.
The healthy and the degenerate, are inextricably interwoven, are one.
It was quite another atmosphere that Shakespeare breathed, an atmosphere .
charged with the dualism of the Middle Ages and earlier times. Good and evil .
then were as the poles asunder. (498-499 Goddardd) .
Macbeth obviously falls into the inescapable pitfalls of evil. Even though Macbeth could be viewed as a victim of evil, as Charles Boyce states in Shakespeare A to Z, "he understood the potential for social and emotional collapse in the absence of morality"(390 Boyce); however, the ideas that caused him to choose evil were not though of by Macbeth alone. .
Throughout the play Macbeth is poisoned with ideas that would lead him down a path of evil. Whether it be from the witches or his own wife, Macbeth was "lead to the water". The moment Lady Macbeth realized Macbeth's intent to become king, she dedicated herself to helping Macbeth achieve this goal, however evil it may be.