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Use east/west instead of left/right and you’ll see there’s no flipping. Left and right are defined with respect to the person, and so they are different for the person and their image. East and west (or up and down) are defined with respect to environment, and they’re not flipped.

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If you use east/west as constants, you will find that the mirror is flipping north and south.

No matter what convention you use to define relative positions between objects, the mirror is physically creating a symmetric image of those, switching distances from closest to farthest from the glass.

That’s a good point, I had not thought of this dimension.

Thank you! So simple, so beautiful of an explanation.

Are you sure? How do you explain the sun in the mirror casting shadows in the opposite direction in the mirror than in the real world? ;-)

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