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other people's affairs; someone else's problem
「人事」 has another reading with different meanings.
彼の失敗を他人事とは思えませんでした。
I can't think of his failure as someone else's problem.
人事ではなく自分のことと考えよう。
Let's think of it as our own matter, not someone else's.
事故のニュースは人事ではないと感じた。
News of accidents is not someone else's business.