A love song is a song about being in love, falling in love, heartbreak upon the ending of a love, and the feelings that these experiences bring. Love songs can be found in the histories and cultures of most societies, though their ubiquity is a modern phenomenon. A highly controversial and startling explanation of the genesis of love songs can be found in Denis de Rougemont's "Love in the Western World". De Rougemont's thesis is that love songs grew out of the courtly love songs of the troubadours, and that those songs represented a rejection of the historical Christian notion of love. A comprehensive list of even the most well known performers and composers of love songs would be a large order. A love song could also be sung by a third person, about two lovers, eg. "Abhishek loves Sara, Sara Kachawalla"