What does Maudie's comparison between Jem and Jack reveal to us about what Jem might really be thinking about Boo and the items left in the tree?
Jem initially tells Scout that the items left in the tree must have belonged to “some bus child,” but before putting the items in his trunk for safekeeping, “…he looked for a long time at the Radley Place. He seemed to be thinking again.” [TKAM, Chapter 4]. Later, when Scout is spending an evening on Miss Maudie’s porch swing, and offers Jem’s opinion that “Maybe [Boo Radley] died and they stuffed him up the chimney,” Miss Maudie responds, “S-ss-ss. He gets more like Jack Finch every day.” [Chapter 5]
Both Jem and Uncle Jack Finch have very similar personalities, depicted in two different stages of life. Jem, like Jack, possesses a sense of bravery, protectiveness, and fair play; though these elements of Jem’s personality are overlaid with a veneer of still-childlike unsophistication. But Jem is growing up, and so his somewhat magical view of the world is changing. He may want to believe in the fantasy and myth surrounding the Radleys, but his developing understanding of the world tells him that Boo is simply a recluse and entitled to his privacy. When he tells Scout the fanciful story that maybe Boo has died and been put in the chimney, he is instinctively protecting both Boo and Scout: Boo from intrusion, and Scout from a loss of innocence.
Scout’s view of the world and of the good and evil in it is still very simplistic. Jem, on the other hand, is developing a grown-up understanding of the world that tells him that most likely, Arthur Radley’s story is far more awful than the legend about the “haint” that lives in the Radley Place. Deep down, he knows the items in the tree were placed there by Boo; but his developing instincts also lead him to protect Boo from “inquisitive children,” and to protect Scout from his nascent understanding that something very terrible must have happened to make Arthur Radley into such a recluse.
In this understanding, Jem reveals himself to be very much like his Uncle Jack Finch. Uncle Jack, like Jem, is a loyal and fair person; but he is also an adult, with a fuller understanding of the unfairness of life and of the horrors that can be perpetrated by humans upon each other. Much like Jem, he resorts to fanciful tales and humor to skirt an issue; but his understanding of the world is far more adult than Jem’s. As an example: in Chapter 9, when Scout abruptly asks Uncle Jack, as he is bandaging her hand, “What’s a whore lady?” instead of answering her question, Uncle Jack instead “plunged into another long tale about an old Prime Minister who sat in the House of Commons and blew feathers in the air and tried to keep them there when all about him men were losing their heads.” Jack is telling a fanciful tale much like Jem would, to distract Scout from knowledge that he feels might harm her.
The comparison Miss Maudie makes is a very astute assessment of Jem’s growing personality and understanding of the world. In making this comparison, it is revealed that Jem knows the items in the tree were placed there by Boo Radley. Jem’s understanding of this, and Miss Maudie’s comparison of him to Jack Finch, also offers us a glimpse of who Jem will be as a grown up: brave enough to face man’s evil, and gentle enough to be a protector of the innocent. In this trait, Jem is very much like his Uncle Jack, and very truly Atticus Finch’s son.