规范性理论的可行性约束——对埃斯特伦德论点的分析

Feasibility Constraint of Normative Theories: A Close Look at Estlund’s Arguments

如果一个规范性理论所给出的指令是不可行的,那么这一理论会因此是错的吗?对这一问题,埃斯特伦德提供了两个论证:'自私比尔论证'和'制度原则论证',这两个论证并不完善,而为了更准确地回答这一问题,区分规范性理论包含的行为指令和制度指令是必要的。在'自私比尔论证'中,埃斯特伦德认为,任何因动机无能而不可行的指令都不因此为假,这个结论并不完全准确。动机上的缺陷,作为一种阻碍因素,可以在对制度指令产生可行性约束并使其为假的同时,对行为指令的真值不产生影响。在'制度原则论证'中,埃斯特伦德认为,如果一个指令在最有利的情况下,仍然不可行,那么这一指令也不必然为假。埃斯特伦德的结论无误,但论证过程有待修缮。对于满足如下形式的理论C=应做A与应做B如果事实D,事实D的真假,不影响C的真假,事实D不对C产生可行性约束。

When the prescriptions produced by a normative political or moral theory are infeasible,is the theory flawed as a result?Estlund provides two arguments to answer this question:'Selfish-Bill Argument'and'Institutional Principle Argument'.However,there are imperfections in both arguments.In order for a clearer and more accurate understanding of the question,it is necessary to distinguish institutional prescriptions from behavioral prescriptions.Regarding the'Selfish-Bill Argument',Estlund argues that a normative theory is not false if its prescription is infeasible due to motivational incapacity.But,the theory could be false if the prescription rendered infeasible by motivational incapacity is an institutional prescription.In the'Institutional Principle Argument',Estlund argues any theory taking the form of'institutional principle'needs not be false,even if its prescription is absolutely infeasible.Estlund’s conclusion is correct but his argumentative steps are problematic.For an institutional principle C=ought A and ought B if fact D,even if D is always false,C can still be true.