How is passion stronger than reason in Macbeth and To Kill a Mockingbird?

Passion is a very strong emotion and is responsible for
many irrational choices and poor outcomes, although it is also the driving force behind
many successes. It is a pity that the passion that Macbeth and Lady Macbeth exhibit in
Macbeth is the destructive type. Similarly in To Kill a
Mockingbird, Tom's guilty verdict and his death together with the reaction of
the townsfolk towards Atticus and his children is indicative of an equally damaging
mindset with passionate displays of misplaced anger and terrible
injustice. 

Macbeth is a decorated soldier, noble in battle
and deserving of the title of Thane of Cawdor and even potentially that of king, if the
witches are to be believed. At no time do the witches tell Macbeth to take matters into
his own hands. In fact, when Macbeth recovers his composure, he realizes that it is his
"vaulting ambition" (I.vii.27) which is responsible for his "earnest of success" (133).
He reasons that Duncan is his "kinsman" and his guest. Furthermore, he is the "meek" and
virtuous "subject" of Duncan. Having reasoned all of this, Macbeth resolves to let the
matter go. He does not realize how persuasive his wife can be and how her accusations of
cowardice will become far more offensive to Macbeth than his reasoned decision. The
passion which Lady Macbeth stirs in him will be too overwhelming for him to fight
against despite the chances that he has to stop himself and the visions which, rather
than making him stop, stir him to even greater wrongs and ultimately make him believe he
is invincible.

For Lady Macbeth, there is no contest. Her
decision to remove Duncan from the picture is clear in her mind from the beginning. She
reasons that it is Duncan's own folly that brings him to her home and behaves as if she
is protecting her "battlements" (I.v.37) and so is justified as any good soldier is
presumed to be in battle where success is measured in the "fatal" entrance of the enemy
which is what Duncan represents to her. Her passion for position and for her husband's
rise to be king overrides all logical thought.  

In
To Kill A Mockingbird, Atticus knows that the innocent Tom Robinson
will be found guilty because the townsfolk of Maycomb County are too stifled in their
logic to recognize the truth. There is a "caste system" (ch 13) in Maycomb and the
people continue their obtuse behavior because it has always been like that there.
Despite the fact that they know all about Bob Ewell's reputation and his apparent
physical abuse of his daughter and even though Atticus presents compelling evidence to
vindicate Tom, they still find him guilty. Atticus knows that the best he can do for Tom
is to tell the truth even if Tom "might go to the chair" (ch 15). The people of Maycomb
do not recognize their own hypocrisy and passionately protect what they think is right
even though logic defies their beliefs. Unfortunately, they will not "see the light" (ch
15).