"There's some here [...] who were talking very loud about adventures on the day we sailed from Cair Paravel, and swearing they wouldn't come home till we'd found the end of the world. And there were some standing on the quay who would have given all they had to come with us. It was thought a finer thing then to have a cabin-boy's berth on the Dawn Treader than to wear a knight's belt. I don't know if you get hte hang of what I'm saying. But what I mean is that I think chaps who set out like us will look silly as--as those Dufflepuds--if we come home and say we got to the beginning of the world's end and hadn't the heart go further" (230).
C.S. Lewis' The Voyage of the Dawn Treader is a book about adventure, travel, and most importantly, about not turning back.
The Voyage of the Dawn Treader can be read on a number of levels, but a recurring theme is the idea that we cannot go back. Lucy learns this quite literally as she is flipping throught the Magician's Boo. After reading a truly wonderful story, and wishing to go back and reread it, she discovers "the right-hand pages, the ones ahead, could be turned; the left-hand ones could not" (168). Certain delights may only be experienced once, and we must therefore take them in while they last.
In a more travel-oriented sense, we can relate this theme to Eustace's inner (and outer) transformation. He does not to go to Narnia; he is unwillingly swept away into the painting and onto the Dawn Treader. For a good portion of the book, he is absollutely beastly to the other characters, and it is only when he turns into a beast himself, a dragon, that he begins to understand how his personality is affecting his life. Upon noticing he has become a dragon, Eustace is at first thrilled, thinking he can seek revenge on the characters who had supposedly so mistreated him. However, "the moment he thought this he realized he didn't want to. He wanted to be friends. He wanted to get back among humans and talk and laugh and share things [...] he began to see that the others had not really been fiends at all. He began to wonder if he himself had been such a ncie person as he had always supposed..." (98). Once Eustace has seen the flaws in his character, he is able to make amends and start fresh. From that time on, "he began to be a different boy. He had relapses [...] but most of those I shall not notice" (119-20). The important thing is that Eustace keeps going in the right direction. Despite the fact that he begins the story as an unpleasant little boy has read none of the right books, he is able to change his life, enough so that by the end of the book, everyone can tell he is an almost different person.
In the quote I opened with, the crew of the Dawn Treader has reached the beginning of the world's end and is preparing to make the voyage all the way to the end; unfortunately, some of the men do not wish to partake in the extra step of adventure. Rynelf and Caspian try to convince them, playing into their pathos by reminding them of their original spirit and how much they would undoubtedly regret not taking the few extra steps to accomplish something amazing. They are already so close; how could they think of turning back now?
Lewis is very skilled at taking a children's adventure story and sneaking in themes and points that will subliminally latch on to younger readers but will also ring significant when those readers come back to this book years later. Of course the sailors should not turn back when they have gotten so close to the end of the world. Once we start going on a path, we must continue; where the path goes is not set in stone, but we must keep going ahead, no matter how much we may want to turn around.