there may be more than one entry following soon. i have done a lot of finding lately. i cannot say that I was really looking for something; it was rather that i happened to walk into some truly inspirational stuff. (or maybe i was just able to draw inspiration from the things that i happened to come across.)
the first i want to share with you is the writings of arnold schoenberg. most people know him as the 'inventor' of serial music (composing by using the twelve tone row), and either worship or detest him because of that. by chance i found a little book he wrote that turns out to be a classic work on harmony (the title is Structural functions of harmony). it turns out schoenberg had a deep understanding of classical music and the way in which harmony works in there. he is also able to connect this insight to the human nature and the world around us (for that see his other writings).
the reason i share this with you is that reading this little book completely transformed my way of looking at my approach to harmony, and how it is taught in a lot of jazz theory books.
the difference is maybe best shown by a simple example. let me quote the first sentence of the book: "A triad standing alone is entirely indefinite in its harmonic meaning;". the insight is that the triad gets its harmonic meaning by the chords that precede or follow it. This simple but profound insight is in a way completely absent in a lot of guitar theory books. they communicate a similar idea by specifying the chord names that result of combining a major or minor triad with each of the 12 possible bass notes.
for me the main difference in perspective is that schoenberg statement is about sequence, whereas most approaches to harmony and so-called linear playing are vertical, static, in specifying possibilities for each individual chord. even if the guitar books deal with such sequences (like the inevitable II-V-I cadence) they usually break it up in three parts.
for schoenberg, the fact that it is the sequence which defines the meaning of a triad (or chord) leads into a thorough exploration of tonality. this is his main quest (eventually leading to serialism): what defines tonality, and is there a music possible that lacks tonality? if the answer to that question is yes, it must consist of harmonic sequences that fail to specify precisely the harmonic meaning of the chords that constitute it. serialism is one of the possible method to arrive at such atonal music.
now of course the challenge is to play this on an eight string and make it jump....