Ron Barnette's Zeno's Coffeehouse Challenge #62 Result

Thanks to Zeno's Coffeehouse patrons and to all the new patrons who dropped by the Coffeehouse! ! This challenge prompted over 100 replies, from many countries around the planet, as Zeno's continues to gather a rich and diverse group of patrons. which is most appreciated as we explore the issues! 

I have listed below the original challenge, followed by several respondents' thoughts on the matter. I want to thank ALL respondents for their thoughtful time taken with Zeno's Coffeehouse, and to encourage your continued support, as critical thinking exercises are explored for mental growth and recreation. Minds need exercising with shared, reflective thinking; this is enjoyable and enriching. Help spread the word!

Thanks!...Ron Barnette

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!
Keep up the Zeno's Coffeehouse involvement, as it's good for the mind!

I have encluded a few samples of the replies received, which are representative. Most appreciated! Ron Barnette

Maria in Lisbon, Portugal writes:
comments: First, I have to thank you for all these FUNtastic challenges! Writing you about my thoughts never crossed my mind, but now, Ron, I have to do it.
This is one of my rules in life: THINK IT SIMPLE before you run to a complex explanation.
Mirrors reverse images from right to left because IT IS THE EASIEST WAY TO LOOK AT THEM. Otherwise, you had to be upside down to see them accurately.
May I add a LOL?

Anthony in Savannah, Georgia USA writes:
comments: could the reason lie in ourselves? that we, in fact, use mirrors to see the image of ourself, perfect ourselves to a presentable form. that image that we want to see is reflected in a most nearly perfect (the closest image to perfection that we, as imperfect humans, can develop) and easy-to-see form, for our own egotistical "viewing pleasure". therefor, why would we want a burden, an imperfection on this image by causing the image to be reflected in any other manner but the one we are most satisfied with, the image that we developed to near perfection?

-from anthony d., 16
savannah, ga

Phil in Christchurch, New Zealand, writes:
comments: Mirrors do not reverse images from right to left. If you hold your left hand up in front of a mirror the reflection is still on the left side of the mirror. However, your brain interprets the reflection as being a real person, the two-dimensional image as being a real three-dimensional human facing you, in which case it is their right hand which would be raised.

Fernando in El Paso, Texas USA writes:
comments: we have bi-nocular vision, that is, we have two eyes splitting our vision in left and right vision. this is why we perceive mirrors as reversing images from left to right.

Chris in Oxford, UK writes:
comments: Mirrors, in fact, don't reverse left/right any more than they reverse up/down! The issue here is one of frames of reference, and there are several ways to approach it.

Way one (a bit weak): When someone approaches you, what he regards as 'left' will be on the hemisphere you regard as 'right', and vice versa. However, what he regards as up is what you regard as up, and ditto for down. Let's not forget the third dimension: what's forward for him is backwards for you, and vice versa. Same happens with a mirror (only that you cannot avail yourself of the mirror image's observations short of transposing yourself into his position, which however is something I am not willing to do just yet). Anyway: it seems that the x axis (up/down) is the only anomalous dimension. Because gravity is a fixed frame of reference, it will remain fixed, while the other axes do not have a fixed frame of reference.

Way two (slightly better): A flat mirror creates a two-dimensional picture which recreates a point P' on the plane of the image so that it is the closest possible to the real point P while still being on the plane of the mirror. The result is that the image of your left hand needs to be in the left hemisphere (all from your perspective, of course). If the image of your left hand were on the right hemisphere, there would be at least one depiction (left-left') which has a shorter distance in space between object-object', hence this would not be a flat mirror. You see a chap in the mirror that looks just like you (let's call him you'). You assume that it is identical, but it is not. Here's how: you see yourself, say, wearing a red glove on your left hand, and see you' wearing a red glove on his left' hand. Because it looks just like you, you assume an identity and expect that if you perform an imaginary turn of either you or you' by 180 degs around your x axis, you ought to match up. Bu [unfortunately, the rest of Chris' reply didn't come through. Sorry, but I wanted to include his note...RB]

Troy (a faithful Coffeehouse patron) from Abilene, Texas USA writes:
comments: "Left," "right," "up," and "down" are relative terms--relative to the perspective of the one doing the observing (in this case).  While "up" and "down" seem fairly fixed, because we normally operate in a vertical mode, the ability to move around and view matters from different positions affects how "right" and "left" are interpreted.

For example, suppose two people are sitting at a table, on the east and west sides, respectively.  There are two blocks on the table, a red one toward the north and a black one toward the south.  Looking at the blocks, the person sitting on the east would say that the red block is to the right of the black one.  The person sitting on the west, however, would say that the red block is to the left of the black one.  Neither of them is wrong--from their perspective.

We understand this, and we compensate accordingly.  If I stand facing a person and place my hands on their shoulders, my right hand is on their left shoulder.  But notice that this wording automatically takes that adjustment into account; the hand which I call "right" (from my perspective) is resting on the shoulder that they call "left" (from their perspective).  We learn to function with this rotation of perspective in mind.

A mirror does not rotate a perspective, though.  Instead, it reflects the image in more of a straight-line fashion.  If I stand facing a mirror, with my right side to the south and my left side to the north, then the reflection of my image will show my right side on the south and my left side on the north.  This seems backwards--because when we are facing another individual, we automatically take the rotation of perspective into account.  But this does not happen with the mirror--nothing is rotated.

Take another example.  Suppose I have a sheet of paper with a large letter "E" printed on it.  I am going to look at the letter in a mirror.  I stand in front of the mirror, turn the paper toward the mirror .......... hold on.  I rotated the image.  The mirror doesn't.  The mirror simply reflects the image it received.

So when we say that a mirror "reverses" the image, it really doesn't.  What the mirror does is reflect things that we typically expect to see rotated.  In that sense, the effect presented to us by a mirror is abnormal, and we suspect that the mirror is doing something very strange.  But it's all a matter of perspective.


Lauri (another faithful Coffeehouse patron) from Karkola, Finland writes:
comments: Friend of mine sometimes challenged me and couple of other peoples - at the coffee room at our University's philosophy department - about the concepts of 'left' and 'right'. (Not a situation very different to Mark's situation, indeed!) I think that in Mark's question there is a tacit presupposition which is simply wrong: mirrors DO NOT reverse images from right to left. If you stand in front of a mirror and move your - let us say - left hand, you can see from the mirror that left hand indeed moves. Let us imagine that when standing in front of this mirror on your left side is a wardrobe and on your right side a bed. Move your left hand and, indeed, in the mirror also the hand on the wardrobe's side moves. Only if you think that there is another person in the mirror and try to imagine things from that other person's viewpoint, would it see like his or her right hand moves when you move your left one. But there certainly (most probably?, must be cautious in the philosophy sit

Jemaiel in Tunis, Tunisia writes:
comments: it does! put a mirror in the gound and the skye would be under your feet