The Big Time introduces the "Change War" world in which a vast war is conducted through space and time by "Spiders" and "Snakes," and by humans and extra-terrestrials who have the rare quality of flexibility and alienatedness that allows them to be recruited out of their ordinary life and time into the big time, the world of all times and possibilities. Many time travel stories suggest that one might travel to the Ice Age, mash a blade of grass, and change all history…. But if you think about it, if time travel is possible, then all of time must exist at once in some sense—the past cannot have wholly disappeared if you can get to it, nor can the future be wholly unmade if you can go there and back. This raises the question as to how one can change the future or the past. This also...