After writing the previous post, something called my attention to Plato's allegory of the cave of shadows. It make me think how similar his example of shadows was to the two-dimensional world visualized in the Scientific American article, although he was interested in a completely different issue. The Scientific American article was concerned with the external, physical world, while Plato was concerned with the internal, mental world. For Plato, the two-dimensional world of shadows represented the unenlightened world in which most men live. As they improve themselves they exit the cave of shadows and see the bright, three-dimensional world, but then, I think, Plato argues that after seeing the bright world, leaders have to re-enter the cave of shadows to lead those poor souls with the knowledge they have gained from the outside world. If they stay in the light, they are no benefit to their fellow men.
Although their points are different, it's interesting that thinkers thousands of years apart resorted to the same type of thought experiment, although in one case (Plato's) what is learned in the three-dimensional world benefits the two-dimensional, while in the other (the Scientific American's) what is learned in the two-dimensional world helps explain the three-dimensional. One is concerned with the physical world, while the other is concerned with the metaphysical.
