What are the main themes in Jeanne DuPrau's The City of Ember?

The central conflict in Jeanne DuPrau's The City of Ember can be identified as a character vs. environment conflict.

In the story, the city of Ember was designed by scientists and builders as an underground refuge in hopes of preserving humanity in the case of an apocalyptic event such as a nuclear war. However, the builders designed the city in such a way that it would only last long enough for Earth to recover from the apocalyptic event. The builders speculate that the citizens of Ember should only remain in Ember "for at least two hundred years ... perhaps two hundred and twenty" ("The Instructions"). Therefore, the builders stocked the city with only enough provisions to last approximately two hundred years. The builders also left instructions for the citizens detailing the way out of Ember so that they can return to Earth's surface and begin repopulating Earth. However, since the builders did not want to create any panic or a premature mass exodus from Ember, they also kept the instructions a secret to be maintained by the mayor until the two hundred years had passed. Unfortunately, due to corruption, the instructions were lost, and the time to leave the city is now past due. Ember's power generator is failing, and the city is dangerously low on supplies; both of these problems put Ember in jeopardy of having its own apocalyptic event. Most of the characters in the story are willing to passively do nothing about the situation beyond hoard supplies for themselves and hope to be rescued. Lina and Doon, the protagonists, are the only two characters willing to actively pursue a rescue plan by searching for a way out of the city. As they search, they run into a conflict with the mayor, whom they discover is hoarding supplies for himself and not finding a solution to Ember's problem. They also run into a conflict with many members of society who are willing to keep waiting to be rescued rather than actively pursue solutions like Lina and Doon. Since Lina and Doon are at odds with their failing environment and at odds with the rest of society, we can clearly see that the central conflict in the story is character vs. environment.

But, as Lina and Doon pursue finding a way to save Ember, they battle with their own internal conflicts as well. Once Lina finds what is left of the important-looking paper that had been in the special box, she must battle being frustrated by others who don't see the document as important. Similarly, Doon must battle controlling feeling angry about the situation because, as his father says, anger can lead to "unintended consequences," and Doon must be more constructive if he is going to find a solution to the city's problem (Ch. 6). Both Doon and Lina must also battle with feelings of disappointment when they fail at first to find the door the instructions speak of and feelings of doubt that the instructions are important. All of these are character vs. self conflicts that Lina and Doon must overcome to bring the story to a successful resolution.

The City of Ember, published in 2003, is the first in a series of novels for young adults by author Jeanne DuPrau. There are a number of themes within the story, but here, I will take a look at the importance of the theme of greed.

Many of the characters are guilty of greed in The City of Ember. Mayor Cole, who hoards things away (light bulbs, to be specific), is especially guilty. But, when the Mayor is reported to the guards, it turns out that they are also benefitting from the mayor’s hoard and are as corrupt and as greedy as he is.

He could think of only one other possibility. The guards . . . at least some of them . . . already knew what the mayor was doing. They knew about it and wanted it to stay a secret. And why? It was clear: the guards, too, had been getting things from the storerooms.

Looper also is guilty of greed, as he steals things from the storerooms—things that could help Ember as a whole—and he sells them for huge profits in his own store.

But Looper’s stealing. And Lizzie, he isn’t just stealing things for you. He has a store! He steals things and sells them for huge prices!

Even the sympathetic character of Doon is guilty of the sin of greed, as he desires recognition as a hero from his father.

He wanted to shout to his father, we found the way out! We’re saved! But, he held himself in, for the sake of his own glory.

One of the book's themes is that people must take control of their own destinies if they are to change anything. Life in Ember is rigidly controlled and so tightly structured that it encourages a mindset of passivity. It is only when characters such as Lina and Doon actively seek to find out how to save their community that change finally comes about. In such a dystopian society, most people just put their heads down and try to live as best they can. But Lina and Doon are not satisfied with this. They are fiercely individualistic and know that life can be better for everyone—but only if they actively challenge the existing system and discover the truth about the City of Ember.

What signs are present in Jeanne DuPrau's The City of Ember?

Signs are certainly a very frequent recurring motif author Jeanne DuPrau uses in The City of Ember. One of the most important signs is the "E drawn with curving lines" on the surface of a stone in a cluster of stones along the river in the Pipeworks, right where the "river disappeared into a great hole in the Pipeworks wall" (Ch. 14). Lina and Doon have figured out that this E stands for egress and leads to the way out of Ember.

In chapter 15, after Lina and Doon find the door leading into the boat room, the candles, and matches, they discover other important signs. The one boat in the first room and the metal box is labeled with signs, and Lina assesses that the signs are teaching tools to help the citizens understand the directions on the piece of paper Lina found:

We learn what's what on the one that has signs. "Boat." "Paddles." "Candles." "Matches."

Lina and Doon then fully understand that the river is the way out of Ember and must be traversed using the boat and paddles.

In chapter 19, after they follow the river in the boat, Lina and Doon find the entrance to a path on a rock shelf. On one of the rocks, Doon finds another very important and encouraging sign:

Welcome, Refugees from Ember!
This is the final stage of your journey.
Be prepared for a climb
that will take several hours.
Fill your bottles with water from the river.
We wish you good fortune,
The Builders. (Ch. 19)

Other signs mentioned throughout the book are the date sign that hangs in Harken Square, mentioned in chapter 2; signs in store windows that, as Lina observes in chapter 11, read "'Closed' or 'Open Mon. Tues. Only'"; and signs protestors are using to picket the mayor, which read, "WHAT solutions, Mayor Cole," as mentioned in chapter 12.