Followup: I watched the video, although I must say that's a much different take on multidimensional theory. As to the 2d-3d analogue, the clip of the planes thru the human being followed by the 4-d "worm" says it all. If I were 3d, I may still perceive distance (supposing I had 2 eyes) and therefore the contours, and not just the length from one tangential extreme to another. Presumably just the color on the edge would be visible to me, since there is no way to "sidestep" the current plane and see inside. It's just math. Game Studio gets it, up to #3 (and in a roundabout machine sort of way, #4).