The downfall of Macbeth in Shakespeare's tragedy "Macbeth" can be attributed to many reasons. These reasons include the supernatural forces that Shakespeare included, external forces such as Lady Macbeth, and internal forces - i.e. Macbeth's changing personality and his strong ambition to be King. Together, these forces caused the tragic downfall of Macbeth. .
The first scene provides an initial indication as to what will happen throughout the book. In this first scene the witches provide the "supernatural force" which helps bring about Macbeth's fall. Macbeth, Thane of Glamis, is content with his position, until the three witches inform him of his future: "Hail to thee, Thane of Cawdor, thou shalt be King hereafter." After hearing this, Macbeth and Banquo, his loyal friend, find out that King Duncan has named Macbeth "Thane of Cawdor." They contemplate whether the rest of the prophecy will come true. The witches also advise them that Banquo's son would be King one day. Together, the witches" prophecies provided for the first force which unleashed Macbeth's "black and deep desires". For this reason, supernatural forces were the first influences that brought about Macbeth's fall.
External forces are the next influences in Macbeth's fall. Primarily, Lady Macbeth is the only external force to heavily influence Macbeth to commit the deed of killing King Duncan, and for this reason is an influence in Macbeth's fall. Macbeth's decision to "proceed no further in this business" was not even considered as a possible outcome by her. Lady Macbeth uses all the methods she can to convince her husband to murder King Duncan. She uses Macbeth's love to her as an instrument saying that if he will not kill the king he really doesn't love her. She asks him if he is a man, and tells him that he will be "so much more a man" after murdering Duncan. She gives Macbeth an example of how resolute and cruel he should be telling him that she - a woman who is supposed to be kind and compassionate--would be able to kill her own child with ease.