It's widely agreed upon that repetition is the most effective way to learn something, whether you're a cook, a musician, a doctor, or a school kid. But the notion that repetition could actually bring greater happiness? That has been explored, too. In the 1950s, Martin Gumpert, a German doctor who wrote the book, The Anatomy of Happiness, explained in the book that, "the forming of patterns, of habits, or tastes, of styles, of attachments, of character, the security of happiness depends on the miracle of repetition." A more recent study by cognitive scientist Elizabeth Hellmuth Margulis, director of the Music Cognition Lab at the University of Arkansas, demonstrated that people who listened to music that was repetitive found it to be more enjoyable than music without repetition. The theory is: when we know what to expect, when our brains are anticipating the chorus, we are actually happier.