Strangers May Cheer You Up, Study Says

How happy you are may depend on how happy your friends’ friends’ friends are, even if you don’t know them at all.

And a cheery next-door neighbor has more effect on your happiness than your spouse’s mood.
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“There’s kind of an emotional quiet riot that occurs and takes on a life of its own, that people themselves may be unaware of. Emotions have a collective existence — they are not just an individual phenomenon.”