The “Theory of the degrees”, the Stufentheorie, often attributed to Simon Sechter (1788-1867), can be described as assigning a different function to each of the seven degrees of the scale (or to six of them, the seventh degree being considered a fifth degree without fundamental). The theory is mainly concerned with chord progression, contrarily to Weber’s theory (also at times termed Stufentheorie) that concentrated on chord quality. Sechrter’s theory is presented in the three volumes of Die Grundsätze der musikalischen Komposition, Lepzig, Breitkopf und Härtel, 1853-1854, which, through Bruckner’s classes, was most influential on Schenker and Schœnberg in the early 20th century.
N. Meeùs