1. All things have quality; if not physical, quality of organization and truthfulness (correspondence to reality).
2. If Beethoven were played on a kazoo, it would still be good; thus, aesthetic surface qualities are irrelevant (production, voice, etc).
3. We can measure the degree of complexity, complexity of phrase, use of musical elements, etc., and finally derive artistic meaning.
4. Complexity and aesthetics in art are driven by this expression of artistic meaning.
5. Therefore, that which has artistic meaning is going to have quality.
1. Complexity and logicity of organization is of course secondary to the underlying, less tangible, spirit of a work. Otherwise Boulez would be a better composer than Beethoven. Of course trying to discuss non-tangibles in other forums will end in tears.
2. The structure of a work includes timbre, the sound of an instrument is determined by mathematical relationships between frequencies, therefore instrumentation is not irrelevant.
3, 4 ,5. To my mind artistic meaning is immediate, whilst complexity of structure is an academic concern. Sure there is good music which is structurally intricate, and all good music is structurally coherent, but the complexity of organization on the surface does not in my opinion make the piece valid. There are many underlying factors which go to make up the artistic character of a piece of music, and although all music based on traditional melodic modes has an inbuilt mathematical coherence, these factors are still not evident except to the ear.
Sorry if my last point was slightly convoluted, shouldn't post when I'm drinking