Billy Pilgrim's Slaughterhouse-Five

Slaughterhouse-Five explores fate, free will, and the illogical nature of human beings. Protagonist Billy Pilgrim is unstuck in time, randomly experiencing the events of his life, with no idea of what part he will next visit.
Billy Pilgrim says there is no free will, an assertion confirmed by a Tralfamadorian, who says, "I've visited thirty-one inhabited planets in the universe. Only on Earth is there any talk of free will." The story's central concept is that most of humanity is insignificant--they do what they do, because they must.
To the Tralfamadorians, everything simultaneously exists, therefore, everyone is always alive. They, too, have wars and suffer tragedies (they destroy the universe whilst testing spaceship fuels), but, when