What quotes show Macbeth is a tragic hero?
A tragic hero has to have a great fall. The drama in the epic is derived from watching the hero unwittingly ensnare himself in a trap he can't get out of. As the hero finds himself defeated because of a tragic flaw, the audience experiences what Aristotle referred to as purification or catharsis—the hero's demise sets things right again—he gets what he deserves, and we feel this reaffirmation of our faith in what is right by watching it happen.
It follows that, in order to have a great fall, a tragic hero must have attained some sort of greatness from which to fall. They must come to the realization that they have failed, and that their failure is due to their own weakness. Macbeth achieves political greatness, but it comes at an even greater cost.
When Macbeth sees that his ambitious plan to gain the throne and then hold it is failing, he becomes desperate. This desperation turns into despondency when Lady Macbeth dies. This is when Macbeth utters the “Tomorrow” soliloquy, which concludes with the lines:
It is a tale told by an idiot,
Full of sound and fury,
You can't fall much further than that. Macbeth now believes that life is “nothing.” All of his ambition and ruthless actions have come to exactly that: nothing. Macbeth shortly will fall the rest of the way when he is killed by Macduff.
In order for a character to be considered a tragic hero, some basic criteria need to be met. First, he must come from a noble background. This is true of Macbeth, who distinguishes himself in battle before he even makes his first appearance on stage. Macbeth's valor causes King Duncan to exclaim of him: "O valiant cousin! Worthy gentleman!" (1.2.26).
Second, a tragic hero must suffer a tragic flaw. Macbeth's is his ambition. This is exemplified in Act I, scene 4, when Macbeth contemplates murdering King Duncan: "Stars, hide your fires; Let not light see my black and deep desires."
Finally, a tragic hero must undergo a tragedy. Macbeth certainly does; he suffers the loss of his wife, his ill gotten kingdom, and his life. The totality of his downfall is clear in his last words, found in Act V, scene 8:
I will not yield,
To kiss the ground before young Malcolm's feet,
And to be baited with the rabble's curse.
Though Birnam Wood be come to Dunsinane,
And thou opposed, being of no woman born,
Yet I will try the last. Before my body
I throw my warlike shield! Lay on, Macduff,
And damn'd be him that first cries, “Hold, enough!”
To find an example of Macbeth as a tragic hero, take a look at Act V, Scene V. In this scene, Macbeth has just learned of his wife's death and he reflects on his actions thus far. What is key in this speech is Macbeth's realization that life is not only fleeting, but that all of his actions will soon be forgotten. He comments on the nature of life, for example:
Life's but a walking shadow.
In addition, he notes that the deeds and actions carried out in life will, ultimately, signify "nothing."
The result of this speech is that the reader catches a different glimpse of Macbeth's character. He is no longer the ambitious pretender to the throne, but is, in fact, a victim of the harsh realities of the nature of life. As a result, the audience can sympathize with Macbeth, if only briefly.