I caught a glimpse of a frightening past in this man's life. Not only had he placed himself outside humanity's laws, but he had made himself independent, free in the strictest sense of the word, out of all reach! Who would dare pursue him to the bottom of the seas, given that he could foil any efforts made against him on the surface? (1.10.21)
Aronnax says that Nemo has made himself "free in the strictest sense of the world," but at what cost? How free are you if you can't interact with regular ol', land-dwellin' mankind?
The sea is nature's vast reserve. It was through the sea that the globe as it were began, and who knows if it will not end in the sea! Perfect peace abides here. The sea does not belong to despots. On its surface immoral rights can still be claimed, men can fight each other, devour each other, and carry out all earth's atrocities. But thirty feet below the surface their power ceases, their influence fades, their authority disappears. Ah, sir, live, live in the heart of the sea! Independence is possible only here! Here I recognize no master! Here I am free! (1.10.79)
Nemo defines independence as freedom from tyranny. From men fighting each other. But what if there were a dispute on board the Nautilus? What would Nemo do? Is his captaining style much different from most monarchical rulers' ruling styles, especially regarding imprisonment-without-warning-or-trial?
Part 2 Chapter 1
"Although the Argonaut is free to leave its shell," I said to Conseil, "it never does."
"Just like Captain Nemo," he judiciously replied. "Which is why he should have called his ship the Argonaut." (2.1.32-3)
Conseil's wry comment, in which he compares Nemo to a sea creature that never leaves its shell, suggests that maybe Nemo's freedom isn't complete. Nemo puts limits on his own freedom. His exile is self-imposed.
Part 2 Chapter 8
So it was a sad day I spent, between my wish to regain freedom and my regret at saying goodbye to the marvelous Nautilus and leaving my underwater studies unfinished! [...] What terrible hours I spent, now seeing myself safe on land with my companions, now wishing, despite my rational side, that some unforeseen circumstance would prevent Ned's plans from unfolding. […]
No oath tied us to him: he counted only on the force of circumstances, and not on our word, to bind us to his company for ever. Moreover, all our attempts were justified because of his freely admitted claim to keep us prisoner on board his ship in perpetuity. (2.8.20, 23)
Aronnax gives up physical freedom in order to enjoy a kind of intellectual independence. When Ned proposes an escape, he can't decide which kind of freedom is more important.
"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 makes sure that Aronnax knows he's not just war-mongering on his own accord. He wants Aronnax to know that he's fighting for the freedom of others. But which "oppressed races" is he talking about? And did these people ever ask Nemo to fight for them?
Part 2 Chapter 10
Would I receive a warm reception if I asked for this freedom? Had he not declared, at the beginning and in formal fashion, that the secret surrounding his life demanded that we be kept imprisoned on board the Nautilus for ever? Would my silence over the last four months not appear to him to be tacit acceptance of the situation? Wouldn't raising the subject again cause suspicion which could hinder our plans if some favorable circumstance came up later? (2.10.12)
It's hard to tell if Aronnax is troubled by Nemo's reaction to his potential bid to escape because he's afraid of how Nemo'll react, or if Aronnax is simply trying to put off making a decision. Because he sure does love seeing everything the world's oceans have to offer out of those big, purty sea-viewing windows the Nautilus has.
Part 2 Chapter 12
If I follow my hunch and if I have understood the captain's life, the Nautilus is not only a ship, it must also be a place of refuge for those, like its captain, who have broken all ties with the land. (2.12.13)
Nemo seems a bit like Peter Pan, lording over his own personal, submersible Neverland. Aronnax thinks he's not just any exile; he just may be an organized leader of exiles who are aiming to cause chaos across the globe.
Part 2 Chapter 18
I could understand how a life like this would suit a man who had no regrets about leaving life on shore, a Captain Nemo who was at home here, who went where he wished, and who pursued goals that were mysterious to others and known only to himself; but as for the three of us, we had not been made to break with humanity. For my part, I did not wish my intriguing and original studies to be buried with me. (2.18.7)
Freedom doesn't mean the same thing to everyone. Nemo's idea of freedom is very different from Aronnax's or Conseil's or Ned's. For his part, Aronnax is too selfish to give up his attachments to society and free-fall—um, free-float?—through life. He wants to make a splash (haha) in the scientific world.
Part 2 Chapter 19
An impossible one even for me, but doubly impossible for Ned. Every human being, by the very fact of being human, is worthy of respect. Have you ever asked yourself what plans of vengeance could be engendered by the love of freedom and hatred of slavery in a nature like the Canadian's, what he could think or do? (2.19.58)
A "love of freedom" isn't a totally harmless thing. It can have serious, and even harmful, consequences.
"Dr. Aronnax," said Captain Nemo, "I will answer you today as I answered you seven months ago: he who enters the Nautilus is destined never to leave again."
"But you are inflicting slavery on us!"
"Give it whatever name you wish."
"But everywhere you go the slave retains the right to regain his freedom! And no holds are barred in how he attempts to do this!"
"Who is depriving you of that right?" replied Captain Nemo. "Have I ever thought of binding you with oaths?" (2.19.52-6)
Even in captivity, Aronnax finds some freedom. Here, he toys with the notion that he is free to escape. But he certainly sits around pondering whether or not to leave the Nautilus for a really long time.