26 Nov
2007
26 Nov
'07
3:08 p.m.
Here's a way to exlain the left-right swap to nontechnical folks: Mirrors don't swap left and right at all. Up in a mirror is up for you, down is down for you, left is to the left of you, right is to the right of you. You're just used to seeing people stand facing you, which involves them turning 180 degrees about a vertical axis. Don't believe me? Wear a shirt with words on it: the first letter will be next to your right hand, just as you see it in the mirror. Now let your friend wear it, standing next to you, then turning around to face you. As they turn around, they swap left and right (so that now your left hand is closest to their right hand), and you can read the words as you're used to.