I made up this riddle, so i’m not sure of its validity. But the idea is that there is no rainbow unless there is a human eye to see it. So in a sense, it is man-made. And it appears huge, spanning across the sky many miles across!
In fact, one could argue against me and say that the only place the rainbow actually exists, is inside the eye of the beholder. Then it’s only less than an inch across.
Just another example of the paradoxical nature of the world we live in . . .