Why does a mirror change right and left, and not top and bottom

The mirror has a perfectly flat and smooth surface, so everything in it is reflected directly. If a person faces the reflection directly, then a ray of light, falling into his eye, moves in a straight line and is reflected in a straight line from the surface. The law of reflection applies: the angle of incidence is equal to the angle of reflection.

Attention! The law of wave optics is valid for perfectly reflective surfaces. It is such a surface that a mirror has.

How a mirror displays

Everyone looking at him sees his reflection. If at that time he waved to himself with his right hand, then his reflection would wave to him from the same side. The back left chair in the mirror also stands behind the left. If, on the contrary, a living person becomes face to face, then his right and left will change. In this case, when waving with his right hand, the one standing opposite will make it left.

Why exactly the mirror changes left and right

Why, looking in the mirror, it seems that the reflection is asymmetrical and waves to him not with his right, but with his left hand, and his head and legs remain in their usual places? The point is the law of gravity acting on humanity. Seeing its reflection, in the brain of people there is a mental movement to the place opposite.

Without realizing a report, all earthlings imagine how they walk with their feet, turn, as is characteristic of people, and become opposite themselves. This is where a misleading sense of asymmetry is created. At the same time, in whatever direction of the world they turn, all directions of movement are equivalent for them. A person moves mentally in the position “head - from above, legs - from below”, and he does not represent another position of his body.

The confusion with asymmetry is easier to understand on the example of a sheet with text. A sheet of text turned to the mirror does not reflect it from left to right, but in the opposite direction. Logic in this case deceives people. The text is reflected correctly, as a person holds it relative to his eyes. If you take a transparent sheet with text written in black felt-tip pen and turn it towards you, as expected, then the reflection of the text will be correct and it will be easy to read. In other words, it was not the mirror that turned the sheet over, but the man himself.

Why the mirror does not change the top and bottom

The law of gravity acts on the people of planet Earth, so in their minds there is an axis-perpendicular to the surface of the earth, a parallel to the force of attraction. Therefore, they care about where their legs and head are. All turns are considered by them relative to the perpendicular axis. If earthlings moved relative to the horizontal axis, jumping to the desired point, for example, upside down, it would seem to them that the reflection has its head below and its legs above.

Asymmetry is a psychological illusion expressed by the presence of an axis not in the mirror, but in the human mind, which in turn creates an asymmetric illusion of rotation in space. All together is caused by the presence of pronounced gravity on planet Earth.