Concepts of musical beauty change over time. The origins of harmony—influenced by the Pythagorean mathematical ideal of whole-number ratios—adored perfect intervals in parallel motion. By the time of the Renaissance, imperfect consonances were the aesthetic model. They displaced consecutive perfect intervals with such thoroughness that even today, beginning students of music theory are prohibited from writing parallel perfect fifths and octaves as they learn to master the principles of common-practice music.
To be sure, aesthetic ideals at the beginning of the 20th century differ from those governing today. We have heard medieval, Renaissance, Classical, Romantic, and a plethora of 20th century styles of music. And yet, some aspects of musical beauty transcend time. My purpose in this paper is to begin exploring these ideals of beauty by comparing passages from two compositions written almost a century apart. In doing so, I will focus on the music’s structure, rather than the less tangible affect that music has upon the listener. The sources of the two passages are Arnold Schoenberg’s “Friede auf Erden” of 1907, and Morten Lauridsen’s “O Nata Lux” of 1997.