1. The Futility of His Actions: Macbeth starts to question the pointlessness of his actions. Despite becoming king, he finds that the fulfilment and happiness he sought remain elusive. He realizes that his crimes have only brought him a sense of emptiness and dissatisfaction.
2. Guilt and Hallucinations: Macbeth begins to experience guilt-induced hallucinations. He sees the ghost of Banquo during the banquet, which becomes a constant reminder of his guilt and unseats his sanity.
3. Loss of Control: Macbeth also realizes that his grip on power is slipping away. He becomes increasingly paranoid and feels his authority challenged. This awareness further heightens his anxiety and desperation.
4. Fear of Retribution: Macbeth fears that his actions will eventually catch up with him and lead to his downfall. He worries about the consequences of his crimes and the possible retribution from those he has wronged.
5. Corruption of His Soul: Macbeth understands the profound transformation that has occurred within him. He acknowledges the corruption of his soul and acknowledges the irreversible damage his actions have done to his humanity.
These realizations contribute to Macbeth's mental decline, leading to his eventual downfall. They mark the progression of his character from ambition to guilt, madness, and self-destruction.