In Act 1 Scene 7 , Macbeth is reasoning with himself, starts of the soliloquy by saying that if he knew that all was going to go well, he would kill Duncan without hesitation. The words used in the first sentence helps the reader to recreate the confusion and difficulty with which Macbeth must make his decision, "If it were done when 'tis done, then 'twere well it were done quickly.". He then counts down the reasons why he shouldn't commit this crime, "Bloody instructions return to plague the inventor", this is one of the more selfish reasons. Here Macbeth is saying that he shouldn't kill Duncan because he will surely get punished later on, nothing seems to crawl into his mind at this point.
At the end of this first soliloquy we can see the transition from a loyal man, to one with a mind riddled with immoral thoughts.
The language used in this scene also helps to explain Macbeth' s downfall. This soliloquy is put into two parts. In the first, we see the use of less brutal language: "assassination", "surcease", "the deed". Here Macbeth avoids speaking plainly about what he is about to do. But towards the end of the second however, the language employed takes on a tone which sounds like the witches speech: "bloody", "plague". This shows us that Macbeth is really thinking about committing this act, he is becoming obsessed with the idea of killing the king. This shows that Macbeth has changed and has become a man with a seed of evil in his heart.
In Act 3 Scene 1, Macbeth reveal his deepest thoughts. He feels that it is no use being kind unless he is safe from attack. Hence Macbeth asks that Banquo be dealt with: "Our fears in Banquo' s stick deep". This alone tells us that Macbeth has lost any sort of human logic, and has moved on to an animal where killing is a a must to stay alive, therefore having lost the moral equilibrium that he used to have. This is the part in the play where Macbeth seems to be be developing a schizophrenic quality in his personality.
In Act 5 Scene 5, there is a slow speech. The slow pace of this soliloquy shows us that Macbeth is downhearted, it has a bitter aspect to it.
This is the scene where Macbeth receives the news of his wife's death. Instead of giving a sad soliloquy, Macbeth just hides his real emotions or has no love left for his deceased wife. To not show any sadness or shock proves us that Macbeth is past moral redemption and is stuck in the deep pit of corruption. He has no room in his heart of stone for anything other than things which concern him and his seat on the throne. "She would have died hereafter". Even though at first glance Macbeth seems unfazed by his companion's death, the fact that she died did actually affect him. It caused him to reflect on life. "Tomorrow and tomorrow and tomorrow". He seems to have lost his drive and he might of realized that all this killing was pointless since everyone dies in the end, "to the last syllable of recorded time". At the end of this speech we can see that Macbeth no longer has murder on his mind and seems to want to redeem himself, unlike at the beginning of the play.
