He was convinced of the impermanence of his work.

他确信其工作是暂时的。

《柯林斯英汉双解大词典》

So why then do we reject the impermanence of the ever-changing universe when it comes to our own lives?

所以，为什么我们要拒绝这千变万化的宇宙中的无常，当它来到我们身边时？

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During difficult times, be committed to resolving problems, but also lighten up and ride the waves of impermanence.

不如意时，要有解决问题的决心，也要有放松的心态。

youdao

The Japanese aesthetic called wabi sabi values imperfection, impermanence, the beauty of things that are a little worn.

WSJ: The Green Machine | John Paul Newport on the Masters

It's about learning to accept things like impermanence and living in the moment.

BBC: Spiritual, but not religious

Currently on display are Vineyard's ceramic works -- misshapen animals and bowls built around the idea of "wabi-sabi", a Japanese aesthetic celebrating the beauty of imperfection and impermanence.

BBC: Gateway to the Blue Ridge Mountains