edit: Thank you to all who answered! I’m amazed at how many ways you came up with to answer this.
It doesn’t.
It only flips front and back.
What are you talking about? It clearly flips it inside-out.
Ackshually, it’s outside-in
Mirrors can totally reverse top-to-bottom, you just have to bend over to see it. The left-right bias is based on the way we look behind us, not any property of the mirror.
This takes a little explaining.
A rotation is a reversal through two dimensions at once.
If you turn around to look behind you, you’re swapping front-and-back, AND left-and-right.
If you stand on your head, you’re swapping front-and-back AND top-and-bottom.
Stand facing the way the mirror does, then turn to look into it. You have to do some kind of rotation - a two-dimension reversal - to get there. If you’re a normal human, you’ll twist around, swapping left-and-right as you swap back-and-front. Your left and right ear swap places, your nose and the back of your head swap places too.
But your reflection doesn’t do that.
A mirror only reverses ONE dimension: front-and-back. It’s the equivalent of punching your face out the back of your head: its ears are still on their original sides. You have swapped left and right in order to face in the opposite direction, but your reflection hasn’t - so it’s ears are on opposite sides to yours.
But you can do it the other way.
Stand with your back to the mirror, and bend over and look under your arm (or between your legs) to see your reflection, instead of twisting around.
Hold something with writing on it, and you’ll see: the letters in the reflection are upside-down, but they face in the right direction.
The only reason you don’t see this very often is that it’s a fucking weird thing to do and nobody ever does it.
Just look at the reflection of the sky in a lake (try any Bob Ross painting) to see a mirror reflect top and bottom
Surely you’re joking!
It doesn’t. It actually flips front and back.
Stand in front of the mirror and raise your right hand. In your imagination, trace the rays of light bouncing off of your hand, bouncing off the mirror, and entering your eyes. Your right hand is in front of the right half of the mirror (as you look at it) not the left half.
Your head, however, is on the top half of the mirror as you look at it, and your torso is on the lower part. The light is simply bouncing off the mirror at angles that align left, right, top and bottom relative to you.
The image of the human in the mirror appears to be raising the left hand, because your mind has re-oriented that person to assign “left” to that hand. But it’s really just the image of the right hand coming relatively straight back at you. It appears to be the person’s “left” hand because we think of the image as a person facing towards us. But it’s not a person. It’s just an image of you.
If it helps, move your right hand towards the mirror until it “touches the other guy’s left hand” and then back it off. Do this a few times and it should click what’s going on.
All of this assumes you are standing right side up. :0)
Well, because it doesn’t flip anything. The light just bounces off, thus light from your right bounces back to your right.
Because the mirror doesn’t flip left and right; it flips front and back.
The mirror DOESN’T flip left and right. Imagine an x-axis as a horizontal line across the mirror, a y-axis as a vertical line up/down the mirror, and a z-axis as a line that comes straight out of/into the mirror.
The mirror is actually only flipping that z-axis that comes out of/into the mirror, by reflecting the light back
It reflects your image across the plane of the mirror. This isn’t physically possible with real-world objects, so your brain substitutes the closest real-world transformation that would approximate the same appearance—which is rotating bilaterally symmetric objects about their axis of symmetry. With a vertically-oriented human, that means turning around so your left is on the right and vice versa.
I got you:
When you face someone, why does your left and their left flipped from one another ?
Any object we face are flipped : it’s true also where you are in front of a car from instance … it doesn’t happen when you are inside the car or inside yourself.
if you can see this, you can understand the mirror as well.There is one difference between them though. I can read other people’s shirts.
Oh shit. I just realized, all the shirts are printed flipped so they are legible to other people!
What are you talking about?
Why does a mirror only flip left and right but not high and low?
Tilt your head 90 degrees to one side. Bam! Now it flips up and down.
Does it?
No, the other answers explain why.
Because the mirror flips your eyes!
You got a left and a right eye. Now if you had a top and a bottom eye instead, then the mirror would not flip left and right, but top and bottom.
Buuut… if you had 4 eyes: left, right, top and bottom, then the mirror would flip them all!
Really?
No, of course not really. Just a provoking thought.
The high rated responses are the real ones.
It depends on how you want to think about it. I think Action Lab did the best short video explanation of how your perception of mirrors makes things look flipped.
