According to HappyLove (Sonja Lyubomirsky), acting like you are a Happy Clown, even if you are not happy, can make you happier!
The research shows this is true. The idea is that your face, body, and voice sends signals to your brain, informing your brain that you are happy, which leads to you becoming at least a little happier!
The same is true for other emotions, so be mindful of your scowls
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