Will we be forever young? Perspectives onVagueness

Abstract

Most of the expressions in our everyday languages are vague. This fact implies that some of the principles of logic or of common sense that we regard as obvious and very well established are, in fact, false. Otherwise, we would be forced to accept such absurd claims as that anyone who is 90 years old is young, or that someone who has just one euro is rich. This is known as the Sorites paradox. In this essay we will try to clarify what it means that some expression is vague, and what is the relationship between vagueness and the Sorites paradox. We will present two different perspectives about the source of vagueness, Supervaluationism and Epistemicism. We will describe how each of these theories try to deal with Sorites paradox, and what each of them has to say about what the origin or source of vagueness is. We will also see what each of these theories has to say regarding the truth value of a sentence where we attribute a vague predicate to an individual that is a borderline case; that is, an individual regarding whom we are unable to say whether it falls under the predicate or not.

Key words: vagueness, borderline cases, Supervaluationism, Epistemicism, Sorites paradox.