Hello folks
I am a big admirer of the works of Beethoven. In english I can't describe exactly, why I admire him, but I try it anyway: His music is for me without any doubt the richest and most intensive music in the colourful universe of classical music. Beethoven was able, to put in every of his pieces an immense content of emotions, thoughts and always a new facette of his own development. No other composer touchs me in such a way as Beethoven do.
So far. Now I thought recently about my "favorite Beethove-piece" and I remarked, that I am not able to define and explain my perceptions and so I decided to ask in this forum for a little help to free my mind of the fogs of emotion and to come closer to a deeper understanding of his works. So I call out for every conoisseur and lover of Beethovens (piano) works to tell me his understanding of his "favourite" piece. And when I say "favourite" I do not mean this kind of "favourite" which is used during talking about colours or animals 
One of the pieces which fascinates me the most is Opus 57 Piano Sonata No. 23 "Appassionata", in german "die Leidenschaftliche". But how I mentioned: I could not explain why!!
I would be very grateful if somebody wants to show me his way of understanding Beethoven 
opus57,
This is a really wonderful post. It is so nice to see someone who is interested in understanding brilliant music without necessarily relying on abstract analysis which, in fact, explains very little.
To begin, you have already pointed out the most powerful aspect of Beethoven's music. It seems to me that each great composer has something that is realitvely unique to him or her. This is not to say that other composers do not have this 'somthing' (whatever it may be), but it just means that they do not have it to the same extent. The most striking thing about Beethoven's music, in my mind, is the incredibly diverse emotional range. This is something he worked on expanding throughout his life, which is clearly evidenced by the music.
This said, there is no way of really generalizing why the music of Beethoven is so great; one must investigate each composition on its own, for they are all vastly different. Each sonata, although in sonata form, displays a different working out of this basic formal structure; in other words, no two sonata 'forms' are the same. Perhaps this is why Charles Rosen chose the plural term for his wonderful book entitled "Sonata Forms".
In any case, I can outline a few things that may help you to understand the brilliance of Beethoven's music. Firstly, how are your skills in harmony, counterpoint, and orchestration? Even if they are wonderful, think about Beethoven - his were infinitely more refined (than all of ours). But this is not all, this was simply the mastery of a craft; the same thing can be said of Mozart, Bach, Brahms, etc. But, what goes beyond this, is the richness of imagination. The ways in which Beethoven works out his ideas is remarkable. There is such an incredible palette of colours that come from, one or two (sometimes even three) small ideas. The invention is breathtaking.
People often confuse the notion of complexity with that of quality. Just because someone uses a complicated system does not make their music automatically profoud or wonderful. Think of this analogy: Someone who uses BIG, long words, but never uses them correctly. Even thlough their vocabulary is vast, their syntax is poor. This does not constitute greatness. Beethoven, even though his harmonic language is relatively simple, used it with great precision and a masterful and artful touch. The same can be said of his orchestration and counterpoint; there is nothing 'weird' in these aspects of his music, but they are used with such mastery - a type of mastery that only comes along about once or twice every hundred years.
To explain in detail the things that are so wonderful in the Op.57 sonata would require more space, and comments complete with musical examples. I do not have time at the moment, but I am currently writing a book on this very subject (but in terms of all the Beethoven sonatas) with a professor from the univeristy of Montreal. When we finish the article on Op. 57 I will be sure to send it to you,provided you do not share it with anyone else before consulting me.
I hope this helps, and once again, a really nice post.
- Andrew