From iterated revision to iterated contraction: Extending the Harper Identity
From iterated revision to iterated contraction: Extending the Harper Identity
复制标题
从迭代修订到迭代收缩：扩展哈珀身份
DOI：
10.1016/j.artint.2019.103171
复制
发表时间：
2019
期刊：
影响因子：
--
通讯作者：
J. Chandler
中科院分区：
文献类型：
--
作者：
R. Booth;J. Chandler
迭代信念变化的研究主要集中在修正上，而AGM信念变化理论的另一个主要算子收缩则相对较少。在本文中，我们将展示如何迭代修订的原则，可以进行迭代收缩一般原则被称为“哈珀身份”。哈珀恒等式提供了一个定义信念集的方法，该信念集由以下两个方面产生：（i）初始信念集和（ii）由<$A修正产生的信念集。在这里，我们看的方式来类似地定义concept信念setresulting从收缩由A。在注意到这种最直接的建议会导致琐碎之后，我们提出了一系列有希望的替代建议，以避免这种结果。这个家族的一个成员，涉及理性封闭的运作，被认为是特别富有理论成果和规范吸引力的。
The study of iterated belief change has principally focused onrevision, with the other main operator of AGM belief change theory, namelycontraction, receiving comparatively little attention. In this paper we show how principles of iterated revision can be carried over to iterated contraction by generalising a principle known as the ‘Harper Identity’. The Harper Identity provides a recipe for defining thebelief setresulting from contraction by a sentenceAin terms of (i) the initial belief set and (ii) the belief set resulting from revision by ¬A. Here, we look at ways to similarly define theconditional belief setresulting from contraction byA. After noting that the most straightforward proposal of this kind leads to triviality, we characterise a promising family of alternative suggestions that avoid such a result. One member of that family, which involves the operation of rational closure, is noted to be particularly theoretically fruitful and normatively appealing.