I open here a page that might in turn become the core of a revised "Music Theory" page. I thought however that it would be easier to leave aside for a while the matter of non-Western theory. Also, I may revise at the same time an existing French page on Théorie de la musique occidentale. This is not meant to be my page on this topic, everyone is eagerly invited to contribute. It is recommended also to have a look at User:Hucbald.SaintAmand/Music theory.
I make use of the < ref > system for biblioraphical references for two reasons: (1) I find this system more easy than any other, especially with the popups that show the notes whenever one "hovers" (passes over) their call, also because comments or quotations may be mixed with references; (2) I don't know how to implement other systems, such as the Harvard one which I find awful because it slows down the reading.
Music theory may be defined as the distanced observation of music.[1]. (For more details on this point, see Theory.) It focuses on musical facts and techniques, "on musical materials per se, in order to explain (and/or offer generalizations about) their various principles and processes".[2] As such, it differs from music philosophy, "the study of fundamental questions about the nature of music and our experience of it",[3] i.e. the ontology of music, or from aesthetics of music, more concerned with the beautiful in music and how we perceive it, and with value judgements about it.[4]
The present article concerns Western music theory, a decision taken to avoid problems with a broader definition and with questions raised by the possible existence of a prehistoric or oral theory. There is another article, Music Theory, which illustrates these problems (see also its talk page). That the present article is concerned with Western theory only in no way implies that this theory is more important than any other; some non-Western theories (e.g. Chinese) certainly predate the Occidental one, even in written form. However, because Occidental culture relied so much on writing, the corpus of Occidental theories probably is quantitatively much larger than any other, and much more easily accessible. But no conclusion can be drawn from this fact.
The same choice has been made in the article "Theory, theorists" in the New Grove, which states: