Chapter 5 includes two flashbacks to when Billy was twelve and on holiday with his parents. On this holiday, he visits two natural wonders: the Grand Canyon and Carlsbad Caverns. Both experiences are significant because Billy remembers specifically how the magnificence and grandeur of these two wonders makes him aware of his mortality. At the Grand Canyon, for example, he is terrified that he will fall in and wets himself when his mother touches him. When the guide turns out the lights in Carlsbad Caverns, note how Billy responds:
Out went the lights. Billy didn't even know whether he was still alive or not.
These two experiences, juxtaposed as they are to the Tralfamadorean explanation of time and lack of free will, highlights the differences between the human view of the world and the Tralfamadorean view of the world. As the Tralfamadoreans are able to see past, present and future simultaneously, they have an acceptance of their fate that is absent in Billy Pilgrim's fear of dying and his uncertainty about whether he is alive or dead.