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From: brian@digi-g.UUCP (Brian Westley)
Newsgroups: net.philosophy
Subject: Re: Why do mirrors reverse left & right, not up & down?
Message-ID: <130@digi-g.UUCP>
Date: Thu, 2-Feb-84 14:57:22 EST
Article-I.D.: digi-g.130
Posted: Thu Feb  2 14:57:22 1984
Date-Received: Wed, 8-Feb-84 07:22:15 EST
References: <533@bbncca.ARPA>
Organization: DigiGraphic Systems Corp., Mpls.  MN
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"Why do mirrors reverse left & right, not up & down"
Mirrors reverse, period.  You are trying to map the most natural frame
of reference (i.e. imagining yourself stepping through the mirror into
the 'other' person's shoes) onto your reflection, when the two other
mappings (pitching forward into a handstand into the 'other' person's
shoes, or simply stepping forward into his shoes without turning around
to face to same way) now seem to result in a mirror reversing up & down,
or back & front, respectively.  You'll notice that in these mappings,
left & right are not reversed.  If humans were not bilaterally symmetrical,
this would be more obvious.  Fiddler crabs aren't confused by mirrors.
							(signed) Merlyn Leroy