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A Generative and Relational Theory of Music that is more logical, consistent, and coherent than conventional mainstream music theory.

GTheory - A generative and relational theory of Music

Background and Introduction

I became involved in the MusicNovatory approach to music theory through my association with a truly brilliant music theorist, the late Michel Perrault. My exposure to these concepts radically and permanently changed my understanding of, and approach to, music.  Lately, I have been referring to this understanding as "GTheory."

This section of the web site will be devoted to articles, explanations, and other information which will act as a supplement to the MusicNovatory home page which was created mainly by Mr. Perrault, and is now maintained by some of his former colleagues in Montréal.  For now, since this site is just getting started, I would like to share with you, as a kind of "appetizer," excerpts from a letter which I wrote to a music professor at the San Francisco Conservatory of Music back in 2000.   Mr. Perrault ended up giving two guest lectures there in February of that year, and later I was asked to do a series of follow-up presentations.  Following this letter is an article I wrote as an introduction to the theory.

A letter to SFCM Music Professor

Dear [Name of Music Professor],

My name is Gregg Jordan. I was a graduate student at SFCM in '87-'89. [some irrelevant stuff deleted here] I hope you are well. I remember you from my days at SFCM, although I'm sure you would not remember me, since I never had the privilege of being in one of your classes. I did, however, have the opportunity to speak with some of your former students, who informed me that you were acutely aware of the many vague and inconsistent concepts that exist in traditional and current music theory. This leads me to the reason I am contacting you now.

I know of a music theorist from Montréal whose name is Michel Perrault. Mr. Perrault has developed a theory of music known as Pantonal [now known as MusicNovatory] which I, personally, have found to be absolutely mind-blowing. I was lucky enough to have taken a workshop with Michel in the summer of 1983. My feeling now is that I learned more about music during that brief three-week workshop than in all my years of undergraduate and graduate studies in music theory combined (about eight years worth). I know that may sound like an overstatement, but it was a real eye-opener, to say the least! The precision, consistency, order, symmetry, and profundity of this theory left such a strong impression on me that I knew I would have to come back to it some day and learn more. So, about five years ago I tracked this gentleman down and arranged to pay him a visit. Since that time, I have become sort of a "long-distance pupil" via phone, mail and internet, as well as in-person visits about twice a year in which he has been kind enough to set aside entire days from his schedule to devote to answering my questions and helping me to deepen my understanding. During that time we have also developed a very friendly relationship.

So, to get to the point, Michel Perrault will be visiting San Francisco from February 15th through the 25th. I have discussed with him the possibility of putting together a presentation for those who might be interested, and he is all for the idea. The aim would be to introduce the general concepts of the theory, and then go a little bit more in-depth into perhaps just one aspect of the theory in order to show some of the possibilities. I thought that the Conservatory would be an ideal place for such a presentation, first of all because of the sense of connection I feel having studied there, and second of all because it seems to me that the faculty and students there have a very open minded attitude toward new (and possibly revolutionary) ideas. In my experience, this is not always the norm within academic circles.

I know that this is very late notice to put something together, but the format could be very flexible, and I would be willing to do whatever leg-work might be necessary. Perhaps you might be interested in having Michel as a guest presenter in one of your theory classes, or maybe several classes could be combined. In any case, I would love to talk with you about the idea and see what you think the possibilities are and to find out if you or any of your students or colleagues are interested.

Please contact me as soon as you get a chance and let me know what you think. Thanks.

Gregg Jordan (MM Guitar '89)

An Introduction to GTheory [aka MusicNovatory] Generative Theory of Music

by Gregg M. Jordan

    Music is such an incredibly rich and multifaceted phenomenon. As we delve "inside" the music and begin to understand its deeper structures, how they fit together, and how they come into being, we are struck with an overwhelming sense of awe and beauty.

    Many people I meet are quite surprised to learn that the theories of music being taught in the music schools, universities, colleges and conservatories of our day are actually quite inconsistent, unscientific, illogical, and vague. It is not uncommon for people, including musicians, to assume that human beings have already figured out all there is to know about music, and that we understand how it works. "Wow, I thought it was set in stone," one of my students exclaimed recently.

    From an historical perspective, it is not so surprising to find that some fields of human knowledge still have a long way to go. Compare the fields of biology and medicine to what they were a mere 150 years ago. And, less than five hundred years have passed since Galileo Galilei (1564-1642) was put on trial and imprisoned for suggesting that the earth is in motion, and is not the center of the universe. (There is an interesting analogy drawn between music theory and astronomy in an article on the MusicNovatory virtual academy website that you might find enlightening.)

    As it stands today, some areas of human knowledge, particularly the physical sciences, are extremely well developed and well established. In these cases, there are core principles that have stood the test of scientific scrutiny and are, for all intents and purposes, universally accepted. Other areas, such as theories of language, knowledge, mind, etc., are lacking such universally accepted principles.

    There are signs, though, that we are making progress. One particularly interesting example is the theory of generative grammar put forth by linguist Noam Chomsky and others. Chomsky proposes that there is a universal deep structure of language that is an innate aspect of the human mind, common to all. Furthermore, there are transformations that the deep structure goes through as it becomes surface structure, thus producing apparent variations among the different human languages.

    In the 1940's (a decade prior to Chomsky's theories of language), a music theorist by the name of Conrad Letendre had a series of insights that led him to believe that there are universal deep structures at the core of all music, and that there are transformations that these basic structures go through that lead to the eventual surface structure of a piece of music. Letendre's work in the 1940's, '50's, and '60's formed the basis for what is now known as the MusicNovatory theory of music, or, as  I like to call it, "GTheory."

    From approximately 1970 to 2010, the driving force behind this theory was Michel Perrault, a disciple of Letendre's. Perrault's contributions cannot possibly be overestimated. He is responsible for taking the insights of Letendre and developing them into a comprehensive generative theory. In addition, he continued to delve more deeply into the generative structure of this musical "language," and has taken the theory to a level that Letendre himself probably could not have imagined. Perrault is also the primary author of the material found on the MusicNovatory virtual academy web site.

    Other notable contributors are Jean-Claude Bélanger and André Cusson.  Jean-Claude Bélanger, a former colleague of Perrault's, has produced several volumes of introductory polyphonic works for children, and has made important observations regarding melodic structure and symmetry.  André Cusson, also a colleague of Perrault's, was responsible for the tech side of the MusicNovatory web site.

    My first exposure to generative music theory came in 1983 when I attended a workshop given by Perrault as part of a music camp. I came away from this experience with an insight, or at least a glimpse, into the nature of music, which stayed with me throughout the remainder of my post-secondary education. I knew that at some point I would continue my exploration of this intriguing theory.  In 1995, I reconnected with Mr. Perrault, and studied in-depth with him for a period of about five years.  In 2000, I helped set up some guest lectures that Michel presented at the San Francisco Conservatory of Music, after which I was asked by one of the theory teachers to do some follow-up presentations for a few semesters in his music theory class.  After the lectures of 2000, Michel began work on the MusicNovatory website, to which Bélanger, Cusson and I also contributed.  From that point until his death in 2010, I remained in contact with Michel Perrault, and am enormously grateful for the opportunity I had to work with him and learn from him. 

    At this point, you may be asking, "why is this music theory called 'generative,' and what makes it so different from traditional forms of music theory?" Although the upcoming articles in this series will answer those questions more explicitly, I will attempt here to provide some generalized answers.

    The traditional academic music theory being taught today at music schools throughout western civilization is for the most part analytical and historical. It could be summed up as a basically "outside-in" approach. It is concerned with the observation of the exterior, surface level structures that appear in musical works, and with the naming and cataloguing of those structures. From there, it attempts to decipher the relationships between the different structures, and to derive some rules or guidelines as to how they are put together.

    Generative theory, on the other hand, could be described as an "inside-out" approach. It begins with a small number of universal principles (simplicity, regularity, hierarchy, and symmetry), and attempts to discover how the simplest and most basic structures, or building blocks, of the musical language are generated. It then goes on to describe the different possible transformations that operate upon these basic building blocks to generate structures of greater (and greater) complexity.

    In general, traditional theory seems to view music as a human invention, subject to the whims and fancies of individual composers throughout history, and to the stylistic conventions of their particular period. It tends to assume that aspects of music that were manifested earlier in history are more fundamental than those that came later. So, for example, traditional theory tends to view melody as more fundamental than harmony.

    Generative theory, on the other hand, views music as a discovery – a discovery of infinite possibilities arising inevitably from underlying universal principles. This discovery takes place over time, and is not yet complete. Therefore, within any given culture or time period, only some of the possibilities, and perhaps not all aspects of the musical language, are manifested. Stylistic differences are not a result of differences in underlying structure, but have to do with the way the material is "dressed up," in other words, what particular types of transformations and performance practices are favored in a given style and/or period.

   This article was originally written in 2003.  It was revised and updated in 2016.  I hope it has provided an overview of what gTheory is about.  At this time, online educational materials are being planned.  If you would like to stay up to date and be informed as new material is released, send me a message, and I will put you on the GTheory mailing list.