A principle to keep from the book, The Road, would be that people should always stay faithful and no have doubt whenever things are going rough in their life. I say this because there's always a possibility great things to happen from nothing. In the case of the man and the boy in the story, there situation shows that them basically having nothing and trying to make their lives better be traveling many miles by walking to the south.
Another principle to keep from the story would be death because throughout the story the thought of death drive the man and the boy each day to get to where they wanted to go, even though the man dies in the end there was still a lot of drive to stay alive and make the situation him and the boy were in much better than it was.
