"Holden and Miller have got two different views on the ethical use of information. That's very much a current argument.
Holden's my holy fool.
He's an idealist, a man who faces things with this very optimistic view of humanity.
He believes that if you give people all of the information, they'll do the right thing with it, because people are naturally good.
Miller is a cynic and a nihilist.
He looks at dissemination of information as a game you play.
He doesn't have faith in anyone else's moral judgment.
Control of information is how you get people to do what you want, and he doesn't trust anyone else to make that call.
I picked those two characters because they're both right, and they're both wrong."
-James S.A. Corey, Leviathan Wakes, p.570-
That little quote is telling and a lot can be gleaned from it regarding the back and forth chapter and verse throughout the book with each respective chapter labeled Miller or Holden. These character creations have been adapted faithfully and are properly reflected throughout this first season of The Expanse.
As an individual I can't help but find Holden positively infuriating at times, but also admirable. Miller, on the other hand, speaks for me on so many levels and I found personally Miller to be the most relatable character. To each their own as they read this story. The dynamic will be relative depending on the reader.
And still, despite there stark differences there's a little bit of each of them that influences the other. Holden undergoes his own changes throughout Season Two.
There is indeed a character arc for them both in the book and in The Expanse TV series.
For me, Miller is appreciated most. His change and where he arrives at by the end of the book and ultimately in Season 2, Episode 5, Home is a fascinating and sweet journey. To see Miller's concern grow and ultimately see some of his faith restored is nothing short of an odyssey worth discovering for readers and viewers of the series.