For instance, many commentators say that vagueness exists because broad categories ease the task of classification. If I can describe your sweater as red, then I do not need to figure out whether it is scarlet. This freedom to use wide intervals obviously helps us to learn, teach, communicate, and remember. The problem is to explain the existence of borderline cases. The existence of vagueness and ambiguity is much more difficult to explain than generality.
Every natural language is both vague and ambiguous.
However, both features seem eliminable. Indeed, both are eliminated in miniature languages such as chess notation, programming languages, and mathematical descriptions. Vague' and 'ambiguous' are pejorative terms. And they seem to deserve their bad reputations. Every person is a child of someone.