The Voyage of the Dawn Treader
How we cite our quotes:
The others all voted for going on in the hope of finding land. I felt it my duty to point out that we didn't know there was any land ahead and tried to get them to see the dangers of wishful thinking. (5.9)
Eustace's dislike of adventure and the unknown indicates his moral inferiority to his companions. Once he connects with his true nature, with Aslan's help, he will be just as excited to explore the eastern end of the world as everyone else. Fear is a sign of a blemished soul in the world of the novel.
"I hope it will never be told in Narnia that a company of noble and royal persons in the flower of their age turned tail because they were afraid of the dark."
"But what manner of use would it be ploughing through that blackness?" asked Drinian.
"Use?" replied Reepicheep. "Use, Captain? If by use you mean filling our bellies or our purses, I confess it would be no use at all. So far as I know we did not set sail to look for things useful but to seek honour and adventures. And here is as great an adventure as ever I heard of, and here, if we turn back, no little impeachment of all our honours." (12.12-14)
Reepicheep admits that exploration isn't always useful but rather it's an end in itself. The crew of the Dawn Treader aren't just trying to survive; they're going out on a limb, pushing the boundaries of the known world.
"I myself will sit at this table till sunrise."
"Why on earth?" said Eustace.
"Because," said the Mouse, "this is a very great adventure, and no danger seems to me so great as that of knowing when I get back to Narnia that I left a mystery behind me through fear." (13.40-42)
Sometimes Reepicheep takes his drive to explore to extremes. Is it really necessary to sit all night at every table where you find some mysteriously enchanted people? Maybe not, but that's how it goes in The Voyage of the Dawn Treader.