One of the reasons for thinking it's not clear whether the argument fails or not is because it's hard to pin down, where exactly did it go wrong?

并不能确定这个论证是否成立,的其中一个原因就是,我们很难确定,到底是哪里出了问题

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It's more difficult to pin down where it goes wrong.

这个论证更难分析出,哪里有错。

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The interesting thing about Descartes' argument is that it's easy to see something has gone wrong in the case of the Morning Star and the Evening Star, but it's difficult to pin down what exactly went wrong.

笛卡尔论证的奇妙之处在于,我们能明显感觉到,晨星和昏星的例子中,有些东西不对劲,但很难确定,错误到底在出哪里

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