Is it or isn't it true that those things which are eternal or non-physical can only be grasped by something that is itself eternal and non-physical?

我们是否可以说,那些永恒,或非现实的事物只能被,本身是永恒和非现实的其他事物认知呢

耶鲁公开课 - 死亡课程节选

Or perhaps a better word would be what is it to be reminded of something by something else that resembles it but is not the thing it reminds you of.

更恰当一点的说法是,你是如何因为另一个类似的事物,而不是这个事物本身,联想到这个事物的

耶鲁公开课 - 死亡课程节选

This is an inductive definition.

你不能用事物的本身去定义事物。

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