This paper offers a simple response to the Moral Twin Earth (MTE) objection to naturalist moral realism (NMR). NMR typically relies on an externalist metasemantics such as a causal theory of reference. The MTE objection is that such a theory predicts that terms like ‘good’ and ‘right’ have a different reference in certain twin communities where it's intuitively clear that the twins are talking about the same thing when using ‘good’. I argue that Boyd's causal regulation theory, the original target of the MTE objection, was never vulnerable to this objection. The theory contains an epistemic constraint on reference which implies that either the property that causally regulates uses of ‘good’ isn't different for the twin communities or, in scenarios where the reference is different, the communities diverge in ways where it's not intuitively clear that ‘good’ has the same reference for them.

中文翻译：

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一个简单的逃离道德双生地球

本文对道德孪生地球 (MTE) 对自然主义道德现实主义 (NMR) 的反对做出了简单的回应。NMR 通常依赖于外部元语义学，例如参考因果理论。MTE 的反对意见是，这样的理论预测像“好”和“正确”这样的术语在某些双胞胎社区中有不同的参考，在这些社区中，很明显双胞胎在使用“好”时谈论的是同一件事。我认为博伊德的因果调节理论，即 MTE 反对的最初目标，从来没有受到这一反对的影响。该理论包含对指称的认知约束，这意味着对双胞胎社区而言，因果关系调节“好”使用的属性没有不同，或者在指称不同的情况下，社区在不同的地方出现分歧。