One of my key philosophical notions is that nothing is really real, since reality can only ever be truly manifested in our individual minds. Most people, of course, disagree, including the great philosopher Friedrich Nietzsche who, when offered this proposition on reality by someone in a Berlin bar, went immediately outside and booted a rock down the road with great force, exclaiming "I refute it thus!". Funnily enough, I never thought that proved much, since there was no way he could demonstrate that what he had seen and felt by kicking the rock was the same, or even similar, as everyone else, so it was a case of “and your point is…?”. Anyway, one thing is certain and that is that the position and appearance of a rainbow is entirely determined by who is looking at it and from what perspective. You can test this yourself by watching a rainbow as you are on the move, it moves with you, so if you ask “where is it then?” the answer is nowhere and everywhere, or, better than that, the rainbow is simply where your perception says it is. You could also try to get the other side of a rainbow (but you would be wasting your time, as you can't get the other side of nowhere). In other words, a thousand people, will see a thousand different rainbows. QED.