I have been studying music theory for some time now and I have become genuinely interested in the genealogy of music theory. I keep asking why when I study even the most basic of theories. For example, only to give a naive example, why is the major mode constructed in the way it is? Why do we have seven notes and why haven't we moved beyond twelve-tone equal temperament?
Is there a source/book/article that addresses such questions in depth?
My view might be flawed, but I truly believe a person such as Iannis Xenakis who writes a book called Formalized Music must have an impeccable understanding of such concepts.