"And in the dream I knew he was going on ahead. He was fixin' to make a fire somewhere out in all that dark and cold. And I knew that whenever I got there, he'd be there. Then I woke up."
Whew. The Coens sure know how to end a movie, right?
Sheriff Ed Tom Bell has spent the entire film trying to figure out whether there's any deeper meaning to his life or to human life in general. Now that he's retired from law enforcement, he has a dream in which his father carries fire deep into a midnight desert until Ed Tom can't see him anymore. The image symbolizes the death of Ed Tom's father and Ed Tom's need to believe that somewhere on the other side of life, his father is still out there somewhere trying to create a fire against all the darkness and coldness of death.
Ed Tom can't see his father in the world of the dead, but he needs to believe that somewhere on the other side of life there's some source of brightness and warmth. It's a beautiful image of hope flickering amongst a background of despair. But … then he wakes up.
This last line might symbolize several things. It could mean that Ed Tom is waking back up to all the unredeemable horror of human life. Or—for you optimists out there—it could also mean that Ed Tom will take the flickering hope of his dream back into his waking life. As with just about everything in this movie, the Coens want us to know that the only thing giving meaning to our lives is what we choose to believe.