"Dr. Aronnax," answered the captain sharply, "I am not what you call a civilized being! I have broken with society for reasons which I alone have the right to appreciate. So I do not obey its rules, and I ask you never to invoke them in my presence again!" (1.10.20)
If Nemo doesn't like the laws of "society", how can he expect anyone to follow his own rules onboard the Nautilus? Could the Nautilus be considered its own mini-society? Do you think Nemo is hypocritical? If so, how is he hypocritical? If not, why not?
No man alive could demand from him an account of his works. God, if he believed in Him, and his conscience, if he had one, were the only judges to whom he could answer. (1.10.21)
Although he doesn't say it outright, Aronnax suggests that Nemo might not even believe in God or have a conscience. If that last bit is true, dude is a sociopath and Arronax should've gotten the heck off of his sub a long time ago. So why didn't he? What keeps Arronax onboard with Nemo?
Part 2 Chapter 3
I began to reflect upon the incidents of our excursion to Mannar Bank. Two reflections inevitably followed. One was the outstanding bravery of Captain Nemo; the other his devotion to a fellow creature, a representative of the human race that he shunned under the seas. Whatever he might say, this strange man had not yet totally succeeded in killing his heart.
When I said as much to him he replied, with some little emotion:
"That Indian, doctor, is the inhabitant of an oppressed country. I am his compatriot, and shall remain so to my very last breath." (2.3.87-9)
It seems safe to say that Nemo hates the institutions of man—say, government—more than he hates individual men. He's clearly got a soft spot for this Indian and that one Greek dude. He even seems to like Aronnax, until Aronnax straight-up asks Nemo for permission to leave the Nautilus. We guess misanthropy and an affinity for some particular human beings can coexist after all.
Part 2 Chapter 8
At that moment, my attention was caught by a few etchings on the walls that I had not noticed on my first visit. They were portraits of those great men of history whose lives were entirely devoted to a great human idea: Kosciusko, the hero who fell with the cry Finis Poloniae, Bozzaris, the Leonidas of modern Greece, O'Connell, the defender of Ireland, Washington, the founder of the American Union, Manin, the Italian patriot, Lincoln, who fell shot by a supporter of slavery, and finally John Brown, that martyr to the freeing of the black race, hanging from his gallows, as so terribly drawn by Victor Hugo.
What link existed between these heroic souls and the soul of Captain Nemo? Could I finally solve the mystery of his existence by this collection of portraits? Was he a champion of the downtrodden peoples, a liberator of enslaved races? Had he taken part in the political and social upheavals that had recently marked the century? Had he been one of the heroes of that terrible American Civil War, that frightful but forever glorious battle? (2.8.30-1)
Many of these men gave their lives fighting for freedom. But whose "freedom" is Nemo fighting for? Maybe Nemo steers the Nautilus into the Maelstrom after killing that last warship in an attempt to join the ranks of these other men who made the "ultimate sacrifice" for their causes.
"Never be of any use!" he replied animatedly. "What makes you believe, monsieur, that these riches must be considered wasted if I collect them? Do you think that it is for my own benefit that I take the trouble to gather these treasures? Who told you that I do not put them to good use? Do you think I am unaware there are suffering beings and oppressed races on this planet, wretches to be helped and victims to be avenged? Don't you understand?" (2.8.75)
Nemo seems to have a bit of a chip on his shoulder when it comes to his money. Perhaps he feels guilty for living such a comfortable life under the sea. In any case, he's like an underwater Robin Hood, stealing from rich (shipwrecks and clams) and giving to the poor and oppressed.
Part 2 Chapter 12
Captain Nemo joined us.
"Well, Master Land?" he enquired.
"Well, monsieur," replied the Canadian, whose enthusiasm had diminished; "it was a terrible sight indeed. But I am not a butcher, I am a hunter, and this was just butchers' work."
"It was a massacre of evil animals," said the captain, "and the Nautilus is not a butcher's knife."
"I prefer my harpoon."
"To each his weapon," replied Nemo, staring at Ned. (2.12.117-122)
Nemo apparently believes that other animals are just as capable of evil as human beings. So he deems one group of whales the "oppressors" and the others the "oppressed." When Nemo anthropomorphizes the whales in this way, he adds to our ever-growing-impression that Nemo is way too obsessed with vengeance for his own—or anyone else's—good.
Part 2 Chapter 14
"That is a going a little far, but I do believe we wouldn't have been able to stop our friend [Ned] from harpooning a few of those magnificent cetaceans. And that would have upset Captain Nemo, for he never spills the blood of innocent creatures without good reason." (2.14.34)
"Never say never," are we right? Aronnax may have to revise this statement after watching Nemo's "massacre" of the unidentified warship. Apparently, even experts are wrong… a lot.
Part 2 Chapter 21
"I am the law, I am the justice!" he said. "I am the oppressed, and they are the oppressor! It is because of them that everything I loved, cherished, venerated—country, wife, children, parents—perished as I watched! Everything I hate is there! Keep quiet!" (2.21.59)
Nemo is right to feel wronged by the men who destroyed his family and country, but it's hard for us to say whether his crusade against the "oppressors" is justified. By declaring himself the law, he becomes his own judge and jury.