LitCharts assigns a color and icon to each theme in Twenty Thousand Leagues Under the Sea, which you can use to track the themes throughout the work.
Scientific Discovery and Technological Innovation
Freedom vs. Constraint
Human Intelligence and its Limits
Exploration, Imperialism, and Conquest
Nature vs. Civilization
Summary
Analysis
The next morning, Arronax is awoken at four a.m. for the expedition. As they set off in the boat, none of the men speak. At six a.m., they arrive at the bay where the pearl fisheries are. Nemo, Arronax, Conseil, and Ned all don their special rubber suits, with the oxygen apparatus attached to the backs. With Nemo leading the way, the men swim past many beautifully-colored fish. By seven a.m., they reach the banks covered in pearl oysters. Soon after they begin gathering treasures to bring back with them, Nemo enters a “large grotto” via an arch that looks as if it were manmade. The rest of the men follow him.
The captives’ adventures with Nemo again raise the question of whether it is possible to properly enjoy an experience—even an objectively wonderful one, like diving for pearls in a pearl fishery—while knowing that one will never be able to share this experience with family and friends (or indeed, escape the experience in the first place).
Active
Themes
Literary Devices
In the grotto, the men approach a gigantic mollusk with a pearl the size of a coconut. Arronax reaches out to touch it, but Nemo bats his hand away. Arronax realizes that Nemo has been leaving it to grow, letting it get more and more valuable. Arronax guesses that its current value is already around $2,500,000. They continue on their journey for around 10 minutes, before encountering an Indian fisherman diving for pearls. The man stays underwater as long as possible, then swims to the surface before diving back down again. He is concentrating too hard to notice the others watching him.
Nemo’s multimillion dollar pearl continues the exploration of the question as to whether experiences are worth having if they cannot be shared. It is certainly an extraordinary feat to have found and grown a pearl of this value, yet it remains unclear as to whether Nemo will even be able (or willing) to sell it given that he eschews modern society and luxury. Furthermore, what use is money to someone who lives underwater in exile?
Active
Themes
To Arronax’s horror, the pearl diver suddenly gestures with terror—a shark is circling directly overhead. Just as the shark is opening its jaws to attack the diver, Nemo moves toward it and it turns its attention toward himself. The shark lunges at Nemo, but he nimbly dodges it. Arronax is impressed with Nemo’s bravery. Nemo and the shark become locked in a vicious fight, and the shark’s blood spills out into the water. Nemo is also injured, but just as the shark is about to kill him, Ned kills it with his harpoon. Back on board the Nautilus, Nemo offers his sincere thanks to Ned. As the vessel moves away, it passes the dead body of the shark, and Arronax stares fearfully at its six rows of teeth.
The climactic end to the pearl-diving expedition reveals that all the characters—despite their profound differences—are willing to risk their lives for one another. In Ned’s case, this is somewhat surprising given how much he (justifiably) hates Nemo for holding him prisoner. Perhaps he has begun to develop something akin to Stockholm syndrome, in which a prisoner gradually develops a fondness for their captor. Yet it is also possible that Ned’s killing of the shark is simply the product of his instincts as a harpooner.
Active
Themes
Arronax reflects on what motivated Nemo to intervene so bravely in order to stop the shark from killing the diver. He eventually mentions it to Nemo, who replies that he wanted to defend the diver because, as an Indian, the diver is “a member of an oppressed race” which means that Nemo is “one” with him.
This is a brief but crucial moment in the book. Some interpret it as evidence that Nemo himself is Indian, or that he comes from another colonized population. Of course, it is also possible that Nemo is of European origin and just feels genuine empathy for the man, or that Nemo is “oppressed” in a way that’s separate from his race.