Law, Language and Lexicon.... These are the creations of society, a group of persons.. When and individual tries to deviate from law, invariably he is punished.. When a group which is large enough(can we call it a crowd?) clamours for change or even breaks the law, it becomes a demonstration, agitation or revolution as the case may be.. And when the law is tampered with by the legislature, it becomes an amendment..
When an individual uses a word differently, it becomes a spelling mistake.. When a small group does the same thing it become a slang.. And when a large number does it , may be the language gets changed, or even new languages are born..
In short, legitimacy depends merely on numbers, and perhaps nothing else..