What does Atticus mean when he tells Alexandra that he is “in favor
of preserving Southern womanhood as much as anybody, but not for
preserving polite fiction at the expense of human life”? What is the polite
fiction he refers to, and whose life does it threaten?

Atticus who is a lawyer is true to his profession and he is referring to the fiction of Tom Robinson's guilt.

Explanation:

Atticus Finch is a character from the novel 'To Kill a Mockingbird' who is a lawyer by profession written by Harper Lee. Atticus is having a conversation with her sister Alexandra when he states that he believes in justice, and for him being true and loyal to his words is more important than any kind of tradition.

When Atticus said this, he was referring to Tom Robinson's guilt and whether he really raped a woman or he was just being innocent.

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