Explain the purpose of Mrs. Schachter in the book Night by Elie Wiesel.

Wiesel's work is a stunning display of how human beings
treat one another.  From the most elemental view of ethics, one of his arguments is that
the Holocaust was so fundamentally awful because it was a moment where human beings
stopped listening to one another.  This silencing of voices was evident with the Nazi
treatment of their victims.  Yet, Wiesel is profound in his assertion that the real and
true horror was when victims mirrored the actions of the aggressors and silenced one
another.  It is to this end that Madame Schachter is included.  Huddled with the other
Jewish people from Sighet on the train, Madame Schachter screams that she sees "fire." 
As they did with Moshe the Beadle, the villagers do not listen to her, nor do they pay
attention to her words.  Rather, they silence her, eventually tying her up and gagging
her in order to not hear her voice.  Of course, she was right.  The fire she saw was the
crematorium at Auschwitz.  However, the larger point and the purpose of her inclusion
was to show that the Nazis' true crime was to legitimize the practice of silencing
voices and of intimidating others.  When the victims start to do this to one another in
order to emulate some level of power in a life where they lack it, Wiesel is reminding
us that the study of the Holocaust is historical, but it is just as much a study of the
philosophical study of the ethical treatment of human beings.  In this light, the
inclusion of Madame Schachter's character is what helps to make the work a study of
philosophy and ethics.