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A fun question - why does a mirror swap left and right, but not up and down?
by skookumchuck 10y ago
A fun question - why does a mirror swap left and right, but not up and down?
- infradig 10y agoMirrors don't swap anything. They just reflect light back the way it came. Think about it.
- Dove 10y agoThe mirror doesn't do the swapping - you do. If you hold a piece of paper so you can read it, you have to turn it around to show it to a mirror. Did you turn it up/down? The mirror shows it upside down. Did you turn it left/right? The mirror shows it reversed left/right. When we interact with other people, they are normally rotated horizontally from us, not vertically, so rotating a paper horizontally is appropriate to give them the same view of the object we have. If we typically met face to face with a vertical rotation - one of us standing on his head, but right hands both on the same side, we would think a vertical rotation was the appropriate thing to do to show a paper to someone else, and would wonder why mirrors showed things upside down.
- justincormack 10y agoThey reverse us front to back. Left and right stay in the same place. But as we are symmetric that way, that is a more "natural" interpretation.