"Change one event in the past and you get a brand new future? Erase the conquests of Alexander by nudging a neolithic pebble? Extirpate America by pulling up a shoot of Sumerian grain? Brother, that isn't the way it works at all! The space-time continuum's built of stubborn stuff and change is anything but a chain-reaction. Change the past and you start a wave of changes moving futurewards, but it damps out mighty fast. Haven't you ever heard of temporal reluctance, or of the Law of the Conservation of Reality?"
— Fritz Leiber, Try and Change the Past
"No one can unmake the past. It already happened, there's no 'undo'. Similarly, the future already happened. We just haven't reached it yet."
— Sarda, 8-Bit Theater
