And if it's not really invisible, even there is a notion of invisible such are the things that invisible in that sense can't be destroyed, souls are not invisible in that sense.

如果它不是完全无形的，即使有无形的定义,根据定义有些东西是无形的,无形的东西不可毁灭，但是灵魂在这个意义上不是无形的。

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it's not really invisible in the relevant sense.

根据相关定义它就不是完全无形的。

耶鲁公开课 - 死亡课程节选

By definition I'm going to define gamma by Cp over Cv by definition.

把Cp/Cv记作γ,这完全是定义。

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