It is also successful on the second task a theory of borderline cases must fulfill: it accounts for the phenomenon of tolerance, that it seems that for any object a on D it holds that if it is F, so is its successor, and that there hence appears to be a seamless transition from the cases to which F applies to those to which it doesn’t apply. Suppose the first borderline case of F is an. Then even a crispFa(n) cannot rule out that an may be F. This reflects the fact that with respect to the question whether it is F, an is humanly indistinguishable from the last clearly F object, an-1. As far as any human can tell (discern), it is not the case that Fan-1 but not Fan. The same holds mutatis mutandis for the last borderline case. The reason why there is no noticeable ‘seam’ is that there is a borderline zone between the clearly F cases and the clearly not-F cases in which the uu-Principle applies. Because of (uu), objections like “but isn’t an distinguishable from an-1 in that it is indistinguishable both from the objects that are F and from the objects that are not F?” are unsuccessful. For, because of (uu), even though an, if it is a borderline case, has this double indistinguishability, it still cannot be told apart from objects that don’t have this double indistinguishability, such as an-1.
Top of page Top of page