论Priest对Sorites悖论的模糊解悖方案

Refuting Priest's Fuzzy Solution to the Sorites Paradox

G.Priest在1998-2003年之间有一个对sorites悖论的模糊解悖方案,根据该解悖方案,对含混语言的最佳语意论应该是某种的模糊语意论。在这样的模糊语意论中,边界语句是既真且假的语句,而sorites悖论中所涉及的离断律和等同传递律则不是有效的推论步骤。Priest并试图利用这样的语意论去说明:为什么sorites悖论看起来像是有效的论证,以及为什么切割点的存在尽管必然却违反直觉。我在本文中论证:Priest的模糊解悖方案是一个完全失败的方案,因此最好被放弃。我论证,Priest的模糊解悖方案至少有以下几个主要的问题:它与Priest的真理理论以及双面真理论不兼容、它对于sorites悖论的诊断有特设的嫌疑、它对于sorites悖论为何看起来有效的说明不具有可信度、它对于切割点存在何以违反直觉的说明也不具有可信度、它有将高阶含混性崩塌为一阶含混性之虞。

G.Priest proposes during 1998-2003 a fuzzy solution to the sorites paradox,according to which an appropriate semantics for a vague language should be a fuzzy one and the inferential steps Modus Ponens（MP）and Transitivity of Identity（TI）involved in standard,paradoxical sorites arguments are all invalid.Exploiting this fuzzy semantics, Priest also tries to explain why MP and TI,though invalid,look like valid ones and why the existence of a cut-off point in a sorites series,though necessary,seems counter-intuitive.I argue in this paper that Priest＇s solution is a total failure and should be abandoned.I argue that his solution has at least the following disadvantages：it is incoherent with Priest＇s dialetheism and his own view about truth,its diagnosis of what＇s going wrong with sorites arguments is ad hoc,the explanation of why MP and TI look like valid forms is not very plausible,the explanation of why the existence of a cut-off point is counter-intuitive is also not very plausible,and it seems to conflate higher-order vagueness with first-order vagueness.