Is Miss Brill a round or flat character? Why?

Flat characters are relatively uncomplicated and do not significantly change throughout their story.  Round characters are more complex and they do develop, sometimes in surprising ways. 

Miss Brill does develop a bit during her story, though it's difficult to be certain that she changes enough to qualify as a round character.  At the beginning of the story, she doesn't seem to realize that she is just like the other people at the park who are "odd, silent, nearly all old," and they seem to be unaware that they look "as though they['ve] come from dark little rooms or even -- even cupboards."  Miss Brill doesn't realize that her silent eavesdropping makes her an oddity and that she too lives in a "little dark room -- [...] like a cupboard."  By the end of the story, it does seem that she's developed some awareness of her condition as a result of hearing the young couple's unkind conversation about her.  Miss Brill skips her cake on the way home and is evidently crying when she puts away her fox fur.  However, she doesn't seem to understand that it is her own crying she hears: the narrator says that "when she put the lid on [the fur's box] she thought she heard something crying."  We understand that Miss Brill hears herself, but she does not recognize it, and so she seems not to have developed a complete understanding or sense of self-awareness.

Whether Miss Brill is a complex character is similarly open to interpretation. Miss Brill is an older woman with a well-developed imagination that compensates for her lack of friends.  She does not realize how socially obsolete she is until she overhears a young couple talking rudely about her; at this point, Miss Brill begins to develop some awareness of the way others see her, but her imagination still protects her, to an point, from recognizing the full extent of her alienation. Though her struggle may be representative of something many experience (how often have we disparaged a quality in someone else only to discover that very quality in ourselves?), Miss Brill experiences a complex range of feelings as she struggles with both pain and denial.

Is Miss Brill a round or flat character? Why?

Miss Brill is a round character because a round character is a major character in the story that is influenced by conflict and is actually changed by it.

Throughout the story, the tone of the music mirrors Miss Brill's feelings. To begin she is a people watcher who loves sitting in the park listening to her "music". This day Mansfield narrates:

There were a number of people out this afternoon, far more than last Sunday. And the band sounded louder and gayer.

As the story finishes, she is consumed by a couple who talk poorly about her right in front of her.

"But why? Because of that stupid old thing at the end there?" asked the boy. "Why does she come here at all–who wants her? Why doesn't she keep her silly old mug at home?"

This bursts her spirit. She had thought she was above everyone else and a great observer of all other characters, but alas, here she is judged. It forever changed her attitude from one of happiness to complete melancholy. 

 But when she put the lid on she thought she heard something crying.

How is Miss Brill a round character?

According to E.M. Forster's definition of flat and round characters in his book Aspects of the Novel , a "round" character is defined, among other things, as one that is

[...] extremely realistic, behaving and speaking in a "real life" manner. The character is complex and increases in complexity throughout the story.

We could definitely argue that Ms. Brill is realistic: she is a British expatriate living in France, working as a teacher. Realistic? Yes.

As we delve into the character, we get to know more things about her, which helps us to make connections and see her character traits. We learn that she has peculiar behaviors, such as going to the gardens to people-watch. She also has a penchant to treat an old fur necklet she wears as if it were some kind of pet, which she refers to as "little rogue."

We also learn about what goes through her mind when she goes to watch people. She believes that she is a part of a big play where everyone plays a character. As readers, we also learn that Ms. Brill gets quite overwhelmed with emotion when these things go through her head.

Oh, how fascinating it was! How she enjoyed it! How she loved sitting here, watching it all! It was like a play. It was exactly like a play. Who could believe the sky at the back wasn't painted?

These are all dimensions of her personality that make the reader understand the character at a much deeper level, something that you cannot do with "flat," two-dimensional characters.

Since we are able to learn so much about Ms. Brill from her behavior, we can also make conclusions as to what causes her personality to be the way it is. For example, we learn towards the end that Ms. Brill, and her fur necklet, get mocked by a couple sitting nearby. This hurts her quite deeply. Even when the author does not explicitly say "Ms. Brill was deeply wounded by the comments that the couple made," we can make connections regarding the nature of her character that lead us to conclude that this is how she felt.

But to-day she passed the baker's by, climbed the stairs, went into the little dark room her room like a cupboard— and sat down on the red eiderdown. She sat there for a long time. [...] she unclasped the necklet quickly; quickly, without looking, laid it inside [the box]. But when she put the lid on she thought she heard something crying.

Therefore, the complexity in emotions, behaviors, and the manner in which her character evolves are some of the factors that define Ms. Brill as a round character.

How is Miss Brill a round character?

Miss Brill is a round character (who is a character that is developed and who has distinct character traits) because we are able to gather much about her through the narrator of the story.  We are able to see into the mind of Miss Brill.  This is called omniscience.  The narrator uses a stream of consciousness style, which means we are exposed to a stream of thoughts as they seemingly occur.  They are almost unfiltered, we could say.  Through this type of narration, we are able to see many facets of Miss Brill, which makes her a round character:

 "Miss Brill" is told in a third-person, stream-of-consciousness narrative, a common device in Mansfield's works which serves to heighten the story's psychological acuity and perceptive characterization. Though the narrative is third person, the stream-of-consciousness technique allows the reader full access to Miss Brill's thoughts, but nothing more than Miss Brill's thoughts.

Is Miss Brill's character in Mansfield's "Miss Brill" round or flat based on the story's ending?

Characterization begins at the initial introduction of a character into a story, and the characterization of Miss Brill is no exception. From the beginning, Mansfield presents Miss Brill as a dynamic (changing), round (full range of emotions, reactions, motivations) character:

Miss Brill put up her hand and touched her fur. Dear little thing! It was nice to feel it again. She had taken it out of its box that afternoon, shaken out the moth powder, given it a good brush, and rubbed the life back into the dim little eyes.

She is presented as having emotional reactions; as having changes in motivations and behaviors; as having plans and ambitions. These all establish her as a dynamic and round character. Her range of emotion is shown in reaction to her fur: "Dear little thing! It was nice to feel it again." Her changes in motivations and behaviors are shown in the fact that she had done something before the story opens and now she is undoing it: "feel it again. She had taken it out of its box." That she has plans and ambitions is revealed in her treatment of the fur: "taken it out of its box that afternoon, shaken out the moth powder etc."

Having said this, we can jump to the end and analyze whether her characterization (1) has changed there (which would indicate a serious flaw in Mansfield's craft) and whether (2) Miss Brill is presented in that isolated spot as a round character.

First, the second to last (or penultimate) paragraph, clearly corroborates the analysis of Miss Brill's round, dynamic character presented in the opening lines. We clearly see motivations and that emotions and reactions change with changing circumstances, and we see plans and aspirations. Thus Miss Brill's characterization as a round, dynamic character is consistent throughout.

Second, what does an analysis of the last paragraph show? We see a number of changes in Miss Brill's emotions, behaviors, and motivations. We see that these are directly related to events that occurred at the park. We see that not only have the events changed her character for the present moment, but--based on the way she reacts to her "red eiderdown," her "fur" and the way she cares for the fur--we see strong indications that this unfortunate encounter with two rude and selfish people at the park may have changed her outlook on her life forever: she may have utterly reevaluated her inclusion in society and thus her happiness. This confirms Miss Brill as a round character.

She unclasped the necklet quickly; quickly, without looking, laid it inside. But when she put the lid on she thought she heard something crying.

What are the hidden complexities of Miss Brill's character?

Miss Brill spends most of the story working hard to hide her loneliness and unhappiness from herself. She is the kind of person who practices the art of positive thinking and does her best to see the bright side of everything. She notices how sunny and beautiful the day is as she heads for the park—"brilliantly fine light like white wine splashed over the Jardins Publiques"—and she is "glad" she decided to wear her fox fur wrap. She rhapsodizes about how much she loves her dear little fur, seeming to feel an identity with it. When, at the end of the first paragraph, it occurs to her she feels both "light and sad" she quickly censors the word sad: "No, not sad, exactly." This is the first sign of the hidden complexities within Miss Brill's psyche.

The relentlessly positive attitude continues in the park. No positive detail is too small for Miss Brill to note, such as the band conductor's new clothes. Apparently the band plays the same music every week, for Miss Brill waits expectantly for the part that sounds like a "little chain of bright drops." She looks forward to overhearing conversations. She even sees herself as an actor in a play that is performed every Sunday and imagines people would miss her if they didn't see her there.

She tries to differentiate herself from the other people who come every Sunday to hear the band. She calls them "funny ... silent, nearly all old," and seeming as if they came from "dark rooms or even—even cupboards!"

Despite her relentless cheerfulness and attempts to see her visit to the park as exciting and full of variety, many unsettling hints pile up to suggest the situation is more complex than Miss Brill wants to admit to herself. She is working too hard to be too happy over too little.

Her chipper façade and sense of belonging, her pride in her fox fur, and her fantasy at the idea of being recognized as an "actress" in the "play" of the park is too hard to keep up once she overhears a young couple criticizing her. The young man wonders why she always comes, and why she doesn't keep her "silly old mug" at home. He calls her "stupid" and his girlfriend laughs at the fox fur, saying it looks like a "fried whiting" or piece of fish, possibly a reference to the moth powder still in it.

Miss Brill goes home demolished, though she still isn't in touch with her feelings. All she knows is that she skips her usual piece of cake and that when she puts her fur away in the box—the fur she identifies with—she thinks she hears "something crying." That "something" is probably her, but she is too divorced from her own pain to admit it.

Miss Brill is complex because on one level we want to admire a person who practices positive thinking, but, on another level, her denial is so great and she is repressing so much sadness that we can't help but feel there will a bad outcome, such as her coming home one day and killing herself without quite being aware of what she is doing. She is acting a part and she can't do it forever. We wish she could acknowledge that she is old, lonely, and sad so that she could find better ways of dealing with it than sitting in a park every Sunday pretending everything is fine.