At Wesleyan, years ago, I was a grad student member of a committee charged with designing a "core" sequence of undergraduate theory courses. The program we began to develop still makes a lot of sense to me, having a nice overall shape and being connected to real (and really fine) repertoire. The sequence began with a semester on musical materials and melody, with the focus on western chant, but taking advantage of the world music resources at Wesleyan and also examining aspects of melody in non-western contexts. The second semester was about modality and counterpoint, concentrating on 15th century music — and especially Josquin — thus avoiding some issues of tonality that the usual focus on Palestrina would invite. A third course was to be called Tonality, centered on the late 18th century Viennese style, and the fourth was to deal with Chromaticism and was the least developed of the four.
None of these courses, as we envisaged them, could come equipped with any of the off-the-shelf textbooks then (or now), although Dieter de la Motte's superb Kontrapunkt, had it been available and translated, would have fit well with the Counterpoint course. Jon Barlow, the long-time generalist on the Wesleyan faculty and I joked about a "counterpoint book that would sell a million copies" with the Milleresque title Topic of Counterpoint, and my preferred title for the first semester of materials and melody was Field & Stream.
Of course, — being academe, even at an unorthodox place like Wesleyan — this sequence was never implemented, but that certainly doesn't mean it shouldn't be tried.
The metaphors of Field & Stream have accompanied my work for a long time. (Perhaps it's a fault of mine, and I'd work more efficiently and productively without them, but I seem to need a metaphor to get a hand — or ear, as the case may be — on most ideas before I can make them work usefully and musically.)
A field, in my usage, is an arrangement of available materials. With pitches, for example, this reflects both my work in intonation systems with the elegant graphing techniques for tunings designed by Walter O'Connell and Erv Wilson and a line of working that begins with 12-tone row boxes and arrays and then the charts used by Cage in works of the late 40's and early 50's in which the items are no longer just single tones or pitch classes but often a mixture of single tones and aggregates of various sizes in various isolate, harmonic, and melodic configurations. To these, structured, fields I have added the open or informal fields or collections found in works of the 50's and 60's by Christian Wolff (I seem to remember Christian also describing these as reserves or pools — see, other people use metaphors, too!) .
A stream is complementary to a field, it is cut through the field, as a route of resources consumed. (Path might be the better metaphor, but sometimes the words just stick.) The compositional issues involved in designing such a stream are obvious: do you allow repeat visits to positions on the field? must all resources on a field be consumed or must some resources be held in reserve? are moves made by choice or pattern or chance? are the resemblances or relationships in the field to be ignored or do they create constraints on movement? what is the relationship between single moves and the overall contour of the stream? are there simultaneous streams? if so, how are they related? etc..
Some of my pieces have titles that refer directly to the idea of a field: Field Study, ...finding the edge of the field..., Crossing the Field, Fieldwork, Afar Afield, Farther Afield, and the unfinished The Art of Fielding. I suspect that I'm not yet finished with fieldwork.