Beauty is defined as something that is pleasing to ones eyes. Though the concept of what is pleasing to the eye changes not only from region to region but also from decade to decade . While in ancient ages women with heavy bodies and good hair were appreciated , on the other hand in the era of old hollywood it as all about short hair and extravagance. I believe the concept of beauty in conditioned in ones mind starting when we are born. a child's mind is said to be 'Tabula Rosa' which means and translates to clean slate . Hence, most of its beliefs are adapted from what it is exposed to. Now we all remember watching cartoons, but did you ever noticed that the most appreciated person happens to have the socially approved beauty levels and the most disliked person - or someones who happens to intimidate every other character , happens to have the features of a ugly person as described by the society. Let's take and example- in doraemon - Shizuka who is admired by everyone fits perfectly to the beauty standards of japan , though on the other hand Jeon who manages to intimidate every one is every bit of ugly when it comes to japanese beauty standards.
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All the more we all like watching plays, movies, series and if looked closely most of the time the bad guy is anything but good looking. Lets not forget our childhood fairy tales we are so glamorously narrated have that character we all hates 'ugly' and also defines the features that make the character ugly.
Also not to forget all the monsters,crafty witches and beasts are defined in such a way that even in imagination they seem unpleasant to us. the thing is we are conditioned to associate a set amount of traits as pleasant and rest are associated with dark and dingy colors and behavior, thus making it unpleasant to us.
Thus beauty is something which is conditioned to a human brain, via many tactics none of us realize.