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Those annoying people who are always smiling and laughing? It turns out that the best option may not be to avoid them: According to researchers from Harvard and the University of California, happiness is genuinely contagious. Weirdly, it's not simply that someone's cheerful mood rubs off on you if you're in their company. The happiness levels of people up to three degrees away in your social network—whom you might not even know—influences your own. So go ahead and start cultivating the charmed and fortunate. Just don't tell any West Coasty types that their New Age babble about good vibes and the transferral of emotional energy might actually be true.