How do Hazel and Gus each relate to their cancer? Do they define themselves by it? Do they ignore it? Do they rage at life's unfairness? Most importantly, how do the two confront the big questions of life and death?

Because the book is about youths with a terminal illness, the meaning of life and death is very important to the characters. Throughout the book, Green allows the reader to take on many different points of view on life and death through thoughts and conversations Hazel has by herself, with her mother and father, and with Isaac, Augustus, Augustus's parents, and Peter Van Houten. Most notably contrasting are the points of view of Hazel and Augustus - Augustus believes that to have a good life one must accomplish something tangible, and that after life there is "Something with a capital S" (p.168) Hazel, on the other hand, takes the tack of doing as little harm as she can in the world, rather than focusing on making a large impact either negatively or positively, and does not seem to believe in anything after life. Other characters in the story rely more or less on realism and science versus religion and comforting "Encouragements" to help them cope with the uncertainty of life and death.