Almost everyone thinks "Greensleeves" is a sad song—but why? Apart from the melancholy lyrics, it's because the melody prominently features a musical construct called the minor third, which musicians have used to express sadness since at least the 17th century. The minor third's emotional sway is closely related to the popular idea that, at least for Western music, songs written in a major key (like "Happy Birthday") are generally upbeat, while those in a minor key (think of The Beatles' "Eleanor Rigby") tend towards the doleful.
The tangible relationship between music and emotion is no surprise to anyone, but a study in the June issue of Emotion suggests the minor third isn't a facet of musical communication alone—it's how we convey sadness in speech, too. When it comes to sorrow, music and human speech might speak the same language.More.