Ron Barnette's Zeno's Coffehouse Challenge #62

Mirror, Mirror, on the Wall

When young Mark walked in to the Coffeehouse last week, he asked Charles and Maggie to think about something he experienced as a kid in a barber shop: images while looking at his reflection in a mirror which reflected this back in a mirror which reflected back in the mirror, which seemed to go on forever. Zeno's thoughts on infinity now occurred to Mark, which intrigued him, as he had been reading about the paradoxes of the good pre-Socratic thinker. But what also occurred to curious Mark was another question:

"Why is it that mirrors reverse images from right to left and not from top to bottom?," he wondered.

Why indeed, as Charles and Maggie thought about Mark's question. To new and to faithful Coffeehouse patrons, let's see if we can help young Mark, ok? And thanks, Mark, for this thoughtful challenge, as you pose an intriguing challenge!

Please formulate your thoughts and submit your reasoned responses below...good luck!....Ron Barnette

For your ongoing enjoyment, I thought I'd keep these so-called Impossible Objects on here, as you contemplate the new challenge. I continually receive positive comments from many loyal Coffeehouse patrons. If you locate other good ones, please let me know. Enjoy!...Ron Barnette

Some Impossible Objects

I credit Jim Loy for these marvelous example of so-called impossible objects, which should amuse you faithful Zeno's patrons, who appreciate thought-provoking stimulation.


		1. Asymmetric crate. An M. C. Escher creation, I surmise
		2. The Penrose staircase: Often drawn by M. C. Escher. Clockwise is downstairs forever.
		3. The tribar: Another impossible object by R. Penrose. It's hard to know how to color it, as the interior becomes the exterior.

		4. The Penrose triangle: Another famous impossible object by R. Penrose. This is sometimes called a tribar (see #3, above).

		5. An ambiguous ring...What is the outside? The inside?