以前从未发生，我们无法解释。

It has never happened before. We have no explanation.

youdao

这是反常的。以前从未发生，我们无法解释。

This is unnatural. It has never happened before. We have no explanation.

youdao

我们无法解释延迟的原因。

We cannot account for the delay.

youdao

We make inferences to the existence of things we can't see, when doing that helps us to explain something we can't otherwise explain.

我们推断一些看不到的事物的存在,因为这样做可以便于我们,解释某些我们不相信就无法解释的事情

耶鲁公开课 - 死亡课程节选

So there's not a counterexample, now that we interpret the relevant notion of invisibility as undetectibility.

所以就没有了反例，因为我们给出的无形这个词的解释,是无法检测。

耶鲁公开课 - 死亡课程节选

these things are explained in terms of cognitive systems that we're not aware of.

我们无法觉察到的认知系统,予以解释。

耶鲁公开课 - 心理学导论课程节选