Ken,
Your conceptual problem is due to the fact that a mirror image is NOT a
reverse image. When you look at yourself in a mirror and raise your left
hand, the image in the mirror raises the hand that is directly in front of
yours, not opposite from yours. The reason we think it is opposite is
because we switch our frame of reference 180 degrees to the viewpoint of
the image in which case the image would be raising its "right" hand.
In order to understand a mirror image you must keep your frame of
reference in the same direction, the direction you, not your image, is
facing.
EXAMPLE: consider a license plate ABC 123. If you were facing the car, the
driver (*) would be on your right and you would be reading the license
plate from left to right. The 3 of the license plate would be the
closest to the dirver and the A the farthest.
ABC 123 *
But when you are looking in a mirror, your frame of reference is not
facing the car but facing away from it, so the driver is now on your left
and since the physical postions of the objects have not changed, the 3 is
still closest to the driver and the A is the farthest. So you have:
* 321 CBA
(with the characters reversed, of course).
To make it even simpler, when you say "the driver is on the left where he
should be" your frame of reference is from the driver's viewpoint. If the
driver had x-ray vision to see his license plate, he would see 321 CBA,
exactly what you see in your mirror. This is because you are both facing
the same direction and have the same frame of reference.
For a practical demonstration of this, get an old license plate and hold it
so it is facing away from you. What you will see is the license plate
backwards. Now have someone hold the licence plate behind you and look at
it with a mirror. It is still backwards because you are still facing in
the same direction and therefore keeping the same frame of reference.
Since the terms left and right are relative, which way is left and which
way is right is dependent on your frame of reference.
BTW, I really messed up an experiment by a friend of mine who was
investigating this very subject. She would sit across a table from the
participant and there would be two objects on the table. She would say,
"Pick up the (object) on the left," amd then record which object you
peiced up. I immediately said, "Whose left?" and she couldn't reply since
that was what the experiment was all about...which frame of reference the
participant would choose and that would be corelated to the participant's
personality (intro- or extro-vert).
(The Psych Department won't use me as a subject anymore, I keep blowing
their curves!)
Bruce
56/9 (wondering if anyone noticed the change in one of these numbers)
Sinemet and Mirapex
* I am because I choose to be *
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Bruce G. Warr "Experience is what enables us to recognize
Healthcare Informatics Lab a mistake the next time we make it."
Information Systems Dept.
University of Maryland Baltimore County
http://umbc.edu/~warr/
(V) (410)455-3206
(F) (410)455-1073
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