Im a big admire of Scriabin. Of any mystical/occult sources, I think Scriabin is among the very few whos involvment has the most substance. He is definately one of the most gifted composers who ever lived. His vision was to transform humanity into a nobler being through music.
One of my other favorite composers Sorabji mentioned Scriabin in his book "Mi Contra Fa" in the chapter "Metapsychic motivation in music" (if Im not mistaken). He wrote that all those contemporary english composers who apparently were into theosophy, according to Sorabji, were nothing but what one could expect to come out of the foggy weather there. He was in generel very sceptical and critizised their approach in a pretty harsh language, whereas a composer like Scriabin on the other hand, was one of the most precious inspiration to Sorabji himself. I think its interesting, that he clearly saw something in composers like Scriabin, Busoni and Liszt as distinct from anyone else. What that quality was or how to theorize it, was difficult for him.
Many people have analysed Scriabins Prometheus because of the easy demonstration of the use of his socalled mystic chord. Many, if not all, of those analyses centers around the location of the chord and probably its modulations, but I have never come across any theory of the construction of the chord itself, which I find more essensial to investigate.
On first listening, the "mystic chord" appear hard to analize and a conventional perception of its harmonic functions can seem rather ordinary. It does have a certain character of lightness or weightlessness though, very much resembling the overall character of Scriabins harmony even in his earlier works.
One other important element in Scriabin, that I found, is the way he works with dissonance. When I was 16, I played his 4th piano sonata, which is an early composition very far away from the harmonic language that he later developed. Nonetheless there is one note in this sonata, that I found particularly interesting. I didnt realize at that time, that this was a phenomenon that became very important in Scriabins later work, a gentle dissonance. It seems to me that he created a kind of contemplation to dissonance in order to free it from its gravitational heaviness and make it flow without effort - contemplation of gravity.
That happens through his use of alterated harmonies, which creates two layers of tonality, of which the one layer is only suggestive through the alterations. Then it is possible to have a dissonance in the predominant tonal layer that serves as a consonance in the invisibly suggested layer, and thereby neutralizing the gravity from the one with the other. It all comes down to this: Flying effortlessly!
The only credibility to this theory belongs to that of the scores, as I have no idea exactly how Scriabin was thinking.
Most noticeable you will also encounter his great sense of ressonance. Scriabin is probably one of the only composers that gives you the impression that he wrote more vertical than horizontal. His forms and motifs are simple, but he could write 3 notes with a ressonance unheard of. We usually think of ressonance as something related to the overtone scale. But esotericly speaking, ressonance is the remain of that division between an object and its environment. These two are connected, and that hidden connection gradually emerge from an object as what we call ressonance. In the end of Scriabins life, he started working with color light, and planned to intergrate fragrance, dance, and the movement of the sun into his unfinished Mysterium.
Since ressonance only has a realm as a concept, like duality, as it implies a seperation from the object, I would imagine that a full establishment of a life-intergrated ressonance, would be not only possible but also realistic to achieve.
There is a short documentary on Scriabins Prometheus on youtube: http://www.youtube.com/watch?v=V3B7uQ5K0IU (The music in the beginning is the opening chord of Prometheus played in slowmotion). Its about time, that more people discover the genious of Scriabin.