# 不确定性下的道德决策

> 【EN】Many important debates in contemporary ethics centre on idealized thought experiments in which agents are assumed to have perfect information about the effects of their actions and other morally relevant features of the choices they face. If Abe turns the trolley, one person will certainly be killed; if he does not, five people will certainly be killed (Foot 1967); how the one and the five got into that situation, whether blamelessly or recklessly (Thomson 1976: 210–11), is also a matter of certainty. If Betty conceives a child now, it will certainly have a life that is hard but worth living, while if she waits, her child’s life will certainly be better—and the two choices will certainly result in different children being born (Parfit 1984: 358). These debates, focused on conditions of certainty, often suggest principles that are hard to generalize to conditions of un certainty. … 【中】当代伦理学许多争论围绕理想化思想实验展开，其中行动者被假定对自身行动后果及其他道德相关特征拥有完备信息：扳道岔则确定死一人，不扳则确定死五人，且这些人如何陷入险境也是确定的。词条考察客观的、主观的与前瞻的几种“应当”，伦理学中的期望效用理论，无知与深度不确定性，风险下的道德约束，道德不确定性，以及小概率与极端风险。

- ID: m13262
- 分类: decide
- 领域: 决策科学

## 定义

当代伦理学的许多争论围绕理想化的思想实验展开，其中假定行动者对自己的行动后果以及所面临选择的其他道德相关特征拥有完备信息。该词条考察放弃这一假定后会出现的问题。 脚手架作用：- 期望权衡：按信息状态下的期望后果而非实际后果评判行动 - 视角选择：区分客观应当、主观应当与前瞻应当各指什么 - 稳健取舍：概率不确定时改用不因细微变动而翻转的准则

## 机制

一旦引入不确定性，评价的对象就从实际后果转向行动者信息状态下的期望值。客观应当看事实如何，主观应当看行动者相信什么，前瞻应当看可得证据下的期望。概率本身不确定时，期望值排序不再唯一，决策要改用不精确概率或稳健性准则。

## 练习

1) 区分三种评价：事实上的最优、按行动者信念的最优、按可得证据的前瞻最优；2) 为各选项列出可能结果与概率；3) 计算期望值并检验它对概率估计的敏感性；4) 概率不可靠时改用区间或最坏情形分析。

## 脚手架用法

- 期望权衡：按信息状态下的期望后果而非实际后果评判行动 - 视角选择：区分客观应当、主观应当与前瞻应当各指什么 - 稳健取舍：概率不确定时改用不因细微变动而翻转的准则

[阅读网页](https://thinkingmodels.site/entries/detail/m13262)