What leads to true happiness? Is it long-lasting friendships or landing a job that you’re proud of?

Arthur Brooks, social scientist and happiness researcher, studies the happy feeling and has found many answers to this burning question along the way.

Brooks’ online Harvard course about managing happiness has more than 180,000 enrollees, and he’s published multiple books about the emotion, including his most recent, “The Happiness Files: Insights on Work and Life.”

Though there are many theories about what increases happiness, “every once in a while, people in my profession need to get practical,” Brooks writes in his new book.

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