General Class Axiom 的用途是什么?

What is General Class Axiom used for?

显示一般 Class 公理的例子:

((walksLike some Duck) and (talksLike some Duck)) SubClassOf Duck

这不是给Duck一个充分必要条件吗?

Duck EquivalentTo: ((walksLike some Duck) and (talksLike some Duck))

它们在逻辑上不是等价的吗?我也读过 this article,但我不明白 General Class Axiom 的真正用途。

正如 AKWS 所说,包含仅提供 necessarysufficient 之一。

示例:

A1 instanceOf Duck

A2 instanceOf (walksLike some Duck) A2 instanceOf (talksLike some Duck)

仅使用包含公理,查询:

Duck 实例:A1, A2 walksLike some Duck 的实例:A2

与等价公理:

Duck 实例:A1, A2 walksLike some Duck 的实例:A1, A2