ABSTRACT

The apparent consistency of Sobel sequences (example below) famously motivated David Lewis to defend a variably strict conditional semantics for counterfactuals.

1. If Sophie had gone to the parade, she would have seen Pedro.

2. If Sophie had gone to the parade and had been stuck behind someone tall, she would not have seen Pedro.

But if the order of the counterfactuals in a Sobel sequence is reversed—in the example, if (b) is asserted prior to (a)—the second counterfactual asserted no longer rings true. This is the Heim sequence problem. That the order of assertion makes this difference is surprising on the variably strict account. Some argue that this is reason to reject the Lewis-Stalnaker semantics outright. Others argue that the problem motivates a contextualist rendering of counterfactuals. Still others maintain that the explanation for the phenomenon is merely pragmatic. I argue that none of these is right, and I defend a novel way to understand the phenomenon. My proposal avoids the problems faced by the alternative analyses and enjoys independent support. There is, however, a difficulty for my view: it entails that many ordinarily accepted counterfactuals are not true. I argue that this (apparent) cost is acceptable.

中文翻译：

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海姆数列以及为什么大多数不合格的“Would”-反事实都不是真的

摘要

Sobel 序列（下面的示例）的明显一致性激发了 David Lewis 为反事实辩护的可变严格条件语义。

1. 如果索菲去参加游行，她就会看到佩德罗。

2. 如果索菲去参加游行并被困在一个高大的人后面，她就不会看到佩德罗。

但是，如果 Sobel 序列中反事实的顺序颠倒了——在这个例子中，如果 (b) 在 (a)之前被断言——第二个反事实断言不再是正​​确的。这是海姆序列问题。断言的顺序导致这种差异在可变严格的帐户中令人惊讶。有些人认为这是完全拒绝 Lewis-Stalnaker 语义的原因。其他人则认为，这个问题激发了对反事实的情境主义渲染。还有一些人坚持认为，对这种现象的解释只是务实的。我认为这些都不对，我捍卫一种理解这种现象的新方法。我的建议避免了替代分析所面临的问题，并得到了独立的支持。然而，我的观点有一个困难：它意味着许多通常被接受的反事实是不正确的。我认为这个（表观）成本是可以接受的。