Christopher F. answered • 02/01/20
Macbeth is a tragic figure because while he was once a valiant, loyal subject of King Duncan, he succumbs to his ambition to assume the throne himself. His ambition or lust for power prompts him to plot to murder King Duncan and Duncan's descendants in line to the throne. Macbeth's power-lust eclipses any goodness and reason (caution) within him. He convinces himself (with the help of the witches) of the truth of a prophecy that the throne will ultimately be his. He believes that he need only act in order to realize his ascendancy to the throne. It is this presumption that he can realize his grand destiny if he will only act that seals his doom. Macbeth is actually not quite up to the task-at-hand (murder). He will require his queen, Lady Macbeth's, forceful guidance (She is cold-blooded and without conscience to speak of). Lady Macbeth's ambition and drive to see it through to fruition is the basis of her famous line ("Unsex me here"); Lady Macbeth acts with more forcefulness (a quality viewed as "manly" in Elizabethan times) in a way that Macbeth is incapable of. Macbeth seems to change during the course of the play; however, one can argue that while Macbeth has previously shown courage in battle, he is actually a complex character whose predominant trait is weakness. This weakness holds sway over the courage (as well as devotion to his king) Macbeth once displayed. He emerges as a an all-too-human figure -- a tool to be manipulated rather than one with the force of character or "spirit" capable of merging "purpose" (ambition) with action.
Christopher F.
p.s. The referenced in your question relate to Act IV, Scene I, I believe. If this is the case, it relates to a soliloquy (an "aside") by Macbeth after he has just heard news of Macduff's flight to England. In these lines Macbeth affirms his resolve to merge what lies hidden in his heart with an actual deed (of murder) that will make his dream of becoming king a reality. This speech is intended to show that Macbeth's mind is now consumed by "evil." His statement that he will "crown [his] thoughts with acts" is interesting for the punning use of the term "crown" - but, yes, mostly for its bone-chilling resolve. Again, I do not believe Macbeth demonstrates here a fundamental change in character - but rather a new step in his descent into madness (his mad lust for power). Macbeth seems full of resolve, but it's really, to my mind at least, more a demonstration of a "fit of resolve"... Macbeth's soul was sick from the beginning, from his early plotting (which he tries to substantiate with prophecy on the part of the Weird Sisters) -- to the point where he tries to muster the courage to follow through on his murderous intent. Now, in Act IV, his seeming resolve indicates an evolution of his madness - (as well as his weakness and ignobility of character). He appears fierce and resolute, but Macbeth is delusional, descending more deeply into a state of madness. It becomes increasingly clear Macbeth doesn't have the spine to follow through on his murder plan on his own. He needs the help of his would-be Queen, Lady Macbeth. She is chillingly full of resolve, whereas Macbeth is a man riddled with doubt and fear.02/01/20