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Mirrors only flip in and out, not left and right or up and down.

• webmaven 6y ago
  > Mirrors only flip in and out, not left and right or up and down. This is true, but elides the point that we perceive the flip as left-to-right because we have two eyes arranged side by side. So, if you want a top to bottom flip, just tilt your head 90 degrees.
  • db48x 6y ago
    That’s not true. The classic experiment is to write a word on a piece of paper, then show it to a mirror. You have to flip the paper over to show it to the mirror, and most people flip the paper horizontally. Thus the word will appear to be backwards. Flip it vertically instead and it will appear upside down. The key observation is that the mirror reflected the light from the paper back to us, but it didn’t flip anything; we flipped the paper, not the mirror.