Everything is changing

This is written by my friend's (Ken) friend Yue Fung (the Canadian Roman, the singer). Facebook's translation does not do justice and I try my best to translate
.
Original:

當你明白無常，你就不會張揚。今日華麗風光，明日可能狼藉一場。
當你明白無常，你就不會悲傷。今日愁雲慘澹，明日可能滿天陽光。
當你明白無常，得，有什麼喜。失，有什麼傷，得失在不停轉換中。

當你明白無常，一切都覺得正常。

Hopefully better translated than Facebook's:

When you understand "everything is changing", you won't be boosting your achievements. Today's splendid life could be a mess tomorrow.

When you understand "everything is changing", you won't be sad. Today's gloom could turn into

sunshine tomorrow.

When you understand "everything is changing", you know today's gain could be tomorrow's loss and vice versa.

When you understand "everything is changing", there is no need to react to today's loss, gain, happiness and sadness.

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I bet "Everything is changing (無常)" is Buddhist philosophy.