It won't surprise you when Plato looks for an example of something that is eternal and indestructible his mind immedialately starts thinking about the 3 platonic forms. Take the number 3.

当柏拉图寻求,某种永恒，不可毁灭的东西,作为证明例子的时候,你可能不会觉得奇怪他马上想到了,柏拉图形式，比如说数字。

耶鲁公开课 - 死亡课程节选