@uastronomer @edavies
OK it is simple.

My face facing a mirror.

Right side of my face is seen on right
Left side of my face is seen on left
Top of my face is seen on top
Bottom of my face is seen on bottom

NO REVERSAL AT ALL BY MIRROR.

But if I was facing myself, with no mirror, I would expect that the left side of the face I am looking at would be on the right. That is how it is when we face another person.

So I EXPECT a left/right reversal that I do not see in a mirror.

@uastronomer @revk Exactly, the reversal is through the plane of the mirror - it's just how we conventionally rotate to look at the image which is confusing.

If I'm looking north at a mirror in front of me, so to the north, then the image of my head is still up, of my feet is still down, of my right hand is still to the east and of my left hand still to the west.

However the image of my front is to the south of the image of my back, contrary to my real position.

Similarly with text. If there's some writing on a wall behind me in the above scenario then the round side of a letter 'P' is on the west in both the real world and in the image in the same way that the vertical bit away from the loop is still down.

Because of the north-south swap effect of the mirror, though, we're now viewing the text as if from the south - i.e., though the wall (OK, let's pretend it's text on a window).

Because of the way we tend to walk around in the world we imagine going to look at the other side of the window by walking, rotating about our vertical axis, so now we label left and right the other way round.

@uastronomer@mastodon.monoceros.co.za @revk@toot.me.uk @edavies@functional.cafe A mirror does not reverse text. Your pointing it away from you did that. Consider text written on a sheet of clear plastic. Which way round would you hold it to read it? Now stand in front of the mirror with that sheet parallel to the mirror. Can you read it both off the sheet directly and in the mirror reflection at the same time?