Delusions

There have been at least three characters in the book that have had some form of hallucinations or delusions. Billy, Weary and Wild Bill. Billy and Weary were in the creek bed when BIlly had a hallucination. "Billy Pilgrim went on skating, doing tricks in sweat-socks, tricks that most people would consider impossible - making turns, stopping on a dime and so on. The cheering went on, but its tone was alerted as the hallucination gave way to time-travel.". They are having these hallucinations because of the tragic things that have been going through and all the near death experiences are making them go mad.