Streumer argues that all normative properties are descriptive properties. His first argument is based on the principle that necessarily coextensive predicates ascribe the same property (N), and the claim that there is a descriptive predicate that is necessarily coextensive with normative predicates. From this Streumer concludes that normative properties are identical with descriptive properties. I argue that, even if we accept (N), this conclusion does not follow. Normative properties could only be descriptive properties if there is some descriptive way in which all instances of normative properties are similar. But Streumer does not show that, and the prospects for doing so are, I believe, not good. His second argument rests on the premise that the nature of normative properties cannot depend on which first order normative theory is true. I argue that this premise is false, and that the argument for it does not sit comfortably with (N).

中文翻译：

---

必然同延谓词和归约

Streumer 认为所有规范属性都是描述性属性。他的第一个论点基于这样一个原则，即必然同延的谓词具有相同的属性（N），并且声称存在一个必然与规范谓词同延的描述性谓词。由此，Streumer 得出结论，规范属性与描述属性相同。我认为，即使我们接受（N），也不会得出这个结论。如果存在某种描述性方式使规范性属性的所有实例都相似，则规范性属性只能是描述性属性。但 Streumer 没有表明这一点，而且我认为这样做的前景并不好。他的第二个论点的前提是规范属性的性质不能取决于哪个一阶规范理论是正确的。