Every river has a bridge. And every island town a saint. Often, these are never built, never seen. Much of what is leftover will show the habits of the people who are no longer there. Not just to imagine, but to know what we cannot ever see—how, for instance, a galaxy beyond our deepest possible human travels turns itself in space—is new to us. This we can know, just as we can know how quickly an apple dropped to the ground falls, accelerates. In general, we are much more used to delapidation and decay here on earth. To get from one muddy bank to the other, one might need a ferryman. One will need to have arrived at that very spot where he polls his ferry across the current. Or not. If not, that bridge may someday be constructed. If not, in the middle of the ocean, one day a temple may be erected. If not, there may be other things that must occur. Or not.