Modern science tells us that the world is a large sphere, and mathematics makes plain that on the surface of a sphere there is no edge. One cannot walk across the edge of the Earth as if it were flat, or even as if it were a cube, because there is simply no edge to be found. Perhaps you'll come across a high cliff and think that it must surely be the edge of the world. But you'll discover your error when you reach the bottom and realize that it's not a true edge; the sphere is just a little bumpy. It is a peculiar property of the area of a sphere, that it can be so finite and yet never come to an angle or a limit.
Without a doubt there is no edge of the world, but there is most certainly an end to it. It's not a gaping, menacing hole, or an imposing cliff, or any sort of extra-dimensional void. The end of the surface of the world is to be found on a California highway, and only if you should be so unfortunate as to find yourself there under the most distressing of circumstances.
Most people pass over the end of the world without incident, saved from destruction by the miracle of the automobile, which whisks them along at a mile a minute or more, leaving only time to briefly gaze at the scenery on either side of the road. At rush hour when the movement of cars is much slower (or perhaps halts altogether) you can perceive it a little more, when you feel like you've always been there and that you are never going to leave. But when your car starts moving again and you are once again driving towards your destination you forget all about it. The truth is that the end of the world just doesn't matter when you're moving fast enough, or when you're far enough away. It has little to offer to the life of a man or a woman engaged in some business, and its menace is restricted to its immediate location, so that a person is entirely removed from dread once he's gotten far enough away in either direction.
The end of the world has a power though, which neither science nor mathematics can explain; nor can the automobile preserve a person from in its entirety. No one knows why or when or how, but every so often it will claim a soul who wanders to the end of the world without the benefit of the shield his fellows enjoy. Perhaps his car breaks down and he has no choice but to sit on the shoulder and await rescue. Or perhaps, even more inexplicably, he finds himself on the unfortunate spot having arrived there on foot. Once there he may not remember how he arrived, or what possessed him to come. Nevertheless, it is late afternoon, and he walks along the side of the road at the end of the world.
Strange things have a way of happening to people under these conditions, unless they should be rescued by a compassionate motorist. Left to his own devices, the unlucky person on the shoulder of the road will eventually either leave or vanish, through processes that are completely unknown. Nobody, after all, can experiment in a laboratory with the forces native to a place such as this. When rescue seems remote, the unlucky traveler must walk in whatever direction will lead him to civilization as quickly as possible. Whether he succeeds is not under his control.
If cars are on the road at all, they drive by with no heed to the pedestrian. Nobody, after all, wants to stop on the highway before they reach their destination. Afternoon falls to evening, and if the person has not made significant progress, he can expect his wide open prison cell to begin to toy with his mind. The billboards will expand, even as they fade to a featureless gray. The cars will accelerate, and occasionally honk for no reason. If the landscape could be said to have any life in it before, it will all drain away. It is no illusion or trick of the light. At the end of the world, the laws are very, very different.
At some point, the experience will drive the person mad, with rage at his predicament, with fear at his isolation, with profound regret at his not having tried hard enough to escape. But if he reaches this stage, then his madness is wasted. He's reached the end of the world, and when he gets there nothing matters any more. All the truths he's been taught, about love and God and commerce and motion, are as nothing before the end, and who is to say how much weight they held even in the beginning? At what point the madness consumes him and he disappears forever is unknown. There are no witnesses to the disassembling of the mind, and the disappearance of the body always occurs just out of sight. It is only after the end that the rest of the world takes note of something missing. But nobody wants to stop in the middle of the highway, so the search is short-lived.
This fate is a rare one. Mankind's genius and invention allow him to travel great distances and move from one end of the road to the other with little difficulty. For the lucky person, the end of the world is of no consequence. For some, it represents nothing more than a vague feeling of strange unease as they traverse a road that by all rights should be familiar. Only the most unlucky will lose their footing, fall off the road and tumble into the end of the world.