Living Music?

I've spent the majority of the last two months of silence reflecting on how to make my performances still deeper.  I want to deal with the same life issues that the composer dealt with while and by writing the music.  I listened to a friend of mine playing a piece of Mozart awhile back, and all I recall thinking at that performance was that everything was very beautifully played, but it had no life.  Instead, I saw lots of visual expression.  He moved a lot.  Once I closed my eyes, the life seemed to flee.

What puts life into the music?  My piano teacher tells me about crescendi and diminuendi and pedaling and creating a good sound, but I feel like these aspects of performance, while important, only serve to be successively thicker layers of sophistication heaped upon the piece, further disguising the basic lifelessness of the pianist.

My friend felt the music very deeply, but that feeling was not transferred into the music.  I would even say he understood the music deeply, but he failed to convey that understanding to me.

What I consider to be great composers are the ones who deal with serious issues of life with their music (of course, there is still a prerequisite level of skill to be attained): take Beethoven, for example.  The last five piano sonatas are perhaps his most profound response to the difficulties of life, and one can certainly not convey that meaning in the music without first dealing with the same issues (real or imagined) and, as they say in the theatre world, becoming Beethoven.

I can't speak for how well my friend did this with his Mozart sonata.  I don't know if "being" is all there is to it, but it seems to be a major part of imbuing life into the music.

I'm going to stop there, let it soak into my own soul for a few more years, and then maybe I'll have an idea of the next step to take.