Sooner or later, every person has a stroke of good fortune.
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I love the example from the Web page of this proverb:
Hamlet:
Let Hercules himself do what he may,
The cat will mew and the dog will have its day.
I think it is easier to spot, out of evny, the fortune that is favoring another,
than to sense, from lacking a clear picture, when oneself is fortunate.