Once there was a man who lived in a cave. He had nowhere else to live. He saw the sky, black in the night. The stars were placed exact upon the face of the sky in their places as they had been for the ages of past. Now, as he watched the stars left their places of designation and drew slowly together to form a great circle above his head. A circle of stars rotating in slow majesty and solemnity. The sky beyond the circle showed clear and black. As the man walked across the open ground, so the circle of stars remained above his head as if to follow his progress.
The man went to the King and Queen, and told them that all the stars were but a crown of stars about his head. The Queen went into the night and beheld the sky. The stars were set about in their allotted course.
She returned to the man and asked him, Are you the man who claimed to see a black satin ball of indeterminate size upon a smooth satin black endless plain which rolled without cessation?
The man, unsure of the reception that his answer would bring, lied. No, he said, that was another man who lives in the cave next door.
Bring this man to me, said the queen to the man from the cave, I have harboured a potent vision of the plain and the rolling ball that he has described, and I would talk with him on the subject. I need to understand if there may be a way to determine the scale of the ball and the speed of its rolling. This conundrum is troubling my sleep.
The man, now in an uncertain situation, decided to proceed by saying, Luckily, I have conversed with my neighbour extensively on this subject and we came to the conclusion that it would be impossible to ascertain these facts, unless one could enter the vision and stand beside the path of the ball as it processed across the smooth satin black plain. This would present some danger as one could not be sure of either the size or the speed of the ball until it was getting very close.
If it is that the ball is enormous and travelling at great speed, then one could easily misjudge the situation and be crushed. Also, this would no doubt divert the ball from its path, albeit a tiny diversion if the ball is of a massive proportion. Alternatively, if the ball is tiny, one might stand in its path by mistake. The ball might come in contact with your shoe or foot, were you unshod, either coming to a halt or, should the ball be travelling at a very fast pace, passing through your foot.
The Queen said, This is not helpful, I want to ascertain these things by observation alone, or by further understanding of this vision. Come to me when you have an answer, and I will tell you why the stars have gathered so well in a great solemn circle above your head.
The Guardians of the Cave 