The labels 'superior' and 'inferior' have always existed, in one form or another. These names have been a part of the human psyche throughout all the ages.

Why do humans lack the self - control to not assign generalized labels? This person is mean, so that person is mean. This person is nice, so that person is nice.

Why do we always have to evaluate, measure up, exclude and ostrasize? These people are imbeciles, these people are brilliant. These people are cheaters, these people are honest. These people belong, these don't.

Why do we prejudice and discriminate? This people is  incapable of ruling themselves, this people is meant to rule all others. This people is superior. This people is inferior.

First, a brief definition of the terms.

Superiority is defined by the standards and values held by a particular individual/society and the ability to reach these standards and reproduce these values. Falling short is Inferiority. These standards and values are opinions - which means they are changeable, fallable, stereotyped, and not usually held by those being judged.

The power of an opinion is actually quite amazing. You can think a person inferior because of their nose size - and they have never considered themselves inferior before - and make them view themselves as inferior.

No one is born with these opinions. Nobody is born prejudiced. It's learned. And that's one of the biggest proofs for how wrong and unnatural it is to believe that somebody is inferior.

By the way - unless it's drilled into one from an early age - few people consider themselves/their societies inferior.

A few examples:

Europeans, particularly the English,  held themselves to be above all other races. But the Chinese also considered themselves the top of the racial ladder. Along with Slavic nations. And the Indians of India. Not to mention the Turks of the Middle East.

For some reason it's all too natural to believe that you are superior. Which is the root of the problem. If you are superior (and you must be) somebody's gotta be inferior. 

So why do we judge, ostrasize, discriminate? Simple. Becuase it feeds our ego.

But there's the logical fallacy. The labels of 'superior' and 'inferior' are generalizations. They refuse to allow for the undeniable fact that there is no such plane of existence as full superiority or full inferiority. Just like there is no such earthly thing as ultimate strength or ultimate weakness.

Let me repeat that.
There is NO such thing as full superiority.
There is NO such thing as full inferiority.
But there SHOULD be Equality.

The terms 'superior' and 'inferior' have been thriving for far too long. It's time they went extinct.

Meanwhile, Equality has been lying forgotten in an overgrown mortuary. It's time it was resurrected.