At the conclusion of the modulating bridge, we expect to be in the contrasting key of C minor. Instead, the bridge concludes in the distantly related key of F sharp major... Instead of resolving to the tonic, the cadence concludes with two isolated E pitches. They are completely ambiguous. They could belong to E minor, the tonic for this movement. They could be part of E major, which we've just heard peeking out from behind the minor mode curtains. [He] doesn't resolve them into a definite key until the beginning of the third movement, characteristically labeled a "Scherzo".
In my last post, I lamented the missed opportunity we had to create a true pattern language about software. Perhaps calling it a missed opportunity is too pessimistic. Bear with me on a bit of a tangent. I promise it comes back around in the end.
The example text above is an amalgam of a lecture series I've been listening to. I'm a big fan of The Teaching Company and their courses. In particular, I've been learning about the meaning and structure of classical, baroque, romantic, and modern music from Professor Robert Greenberg.1 The sample I used here is from a series on Beethoven's piano sonatas. This isn't an actual quote, but a condensation of statements from one of the lectures. I'm not going to go into all the music theory behind this, but it is interesting.2
There are two things I want you to observe about the sample text. First, it's loaded with jargon. It has to be! You'd exhaust the conversational possibilities about the best use of a D-sharp pretty quickly. Instead, you'll talk about structures, tonalities, relationships between that D-sharp and other pitches. (D-sharp played together with a C? Very different from a quick sequence of D-sharp, E, D-sharp, C.) You can be sure that composers don't think in terms of individual notes. A D-sharp by itself doesn't mean anything. It only acquires meaning by its relation to other pitches. Hence all that stuff about keys---tonic, distantly related, contrasting. "Key" is a construct for discussing whole collections of pitches in a kind of shorthand. To a musician, there's a world of difference between G major and A flat minor, even though the basic pitch (the tonic) is only one half-step apart.
Also notice that the text addresses some structural features. The purpose and structure of a modulating bridge is pretty well understood, at least in certain circles. The notion that you can have an "expected" key certainly implies that there are rules for a sonata. In fact, the term "sonata" itself means some fairly specific things3... although to know whether we're talking about "a sonata" or "a movement in sonata form" requires some additional context.
In fact, this paragraph is all about context. It exists in the context of late Classical, early Romantic era music, specifically the music of Beethoven. In the Classical era, musical forms---such as sonata form---pretty much dictates the structure of the music. The number of movements, their relationships to each other, their keys, and even their tempos were well understood. A contemporary listener had every reason to expect that a first movement would be fast and bright, and if the first movement was in C major, then the second, slower movement would be a minuet and trio in G major.
Music and music theory have evolved over the last thousand-odd years. We have a vocabulary---the potentially off-putting jargon of the field. We have nesting, interrelating contexts. Large scale patterns (a piano sonata) create context for medium scale patterns (the first movement "allegretto") which in turn, create context for the medium and small scale patterns (the first theme in the allegretto consists of an ABA'BA phrasing, in which the opening theme sequences a motive upward over octaves.) We even have the ability to talk about non sequiturs---like the modulating bridge above---where deliberate violation of the pattern language is done for effect.4
What is all this stuff if it isn't a pattern language?
We can take a few lessons, then, from the language of music.
The first lesson is this: give it time. Musical language has evolved over a long time. It has grown and been pruned back over centuries. New terms are invented as needed to describe new answers to a context. In turn, these new terms create fresh contexts to be exploited with yet other inventions.
Second, any such language must be able to assimilate change. Nothing is lost, even amidst the most radical revolutions. When the Twentieth Century modernists rejected the tonal system, they could only reject the structures and strictures of that language. They couldn't destroy the language itself. Phish plays fugues in concert... they just play them with electric guitars instead of harpsichords. There are Baroque orchestras today. They play in the same concert halls as the Pops and Philharmonics. The homophonic texture of plain chant still exists, and so do the once-heretical polyphony and church-sanctioned monophony. Nothing is lost, but new things can be encompassed and incorporated.
And, mainframes still exist with their COBOL programs, together with distributed object systems, message passing, and web services. The Singleton and Visitor patterns will never truly go away, any more than batch programming will disappear.
Third, we must continue to look at the relationships between different parts of our nascent pattern language. Just as individual objects aren't very interesting, isolated patterns are less interesting than the ways they can interact with each other.
I believe that the true language of software has as much to do with programming languages as the language of music has to do with notes. So, instead of missed opportunity, let us say instead that we are just beginning to discover our true language.
1. Professor Greenberg is a delightful traveling companion. He's witty, knowledgeable and has a way of teaching complex subjects without ever being condescending. He also sounds remarkably like Penn Jillette.
2. The main reason is that I would surely get it wrong in some details and risk losing the main point of my post here.
3. And here we see yet another of the complexities of language. The word "sonata" refers, at different times, to a three movement concert work, a single movement in a characteristic structure, a four movement concert work, and in Beethoven's case, to a couple of great fantasias that he declares to be sonatas simply because he says so.
4. For examples ad nauseum, see Richard Wagner and the "abortive gesture".