"Lost in Translation: Life in a New Language" by Eva Hoffman

There is a passage about piano playing in the above memoir which I find particularly beautiful.

"  Although she never raises her voice, and is unfailingly kind, Pani Witeszczak exercises great authority over me. She is the first in a sequence of music teachers to whom I owe the closest thing I get to a moral education. In this intimate, one-to-one apprenticeship -- an apprenticeship mediated through the objective correlative of music -- they teach me something about the motions and the conduct of my inner life. When Pani Witeszczak attempts to convey to me what tone to use in a Bach invention, or the precise inflection of a theme in a mazurka, she is trying, indirectly, to teach me the language of emotions. "Music is a kind of eloquence," she tells me. "Ask yourself what it says here. See? This is like someone pleading. And here is someone is getting angry, and more and more angry, and trying to persuade somebody else, who is not listening." 
   It is that speech that Pani Witeszczak tries -- by cajoling, by explaining, by guiding my hand -- to tease out of me. Like all teachers in Poland at that time, she emphasizes the importance of tone, and I soon find out why: tone, I discover, is something about which I cannot lie. If I do not feel the kindling of a fire as I play, my tone betrays me by its coldness; if I do not feel the capricious lightheartedness of a scherzo, my tone turns wooden in spite of my best attempts to feign playfulness. By some inexplicable process, the precise nuance of what I feel is conveyed through my arm to my fingertips, and then, through those fingertips, to the piano keys, which register with equal precision the slightest swerve of touch and pressure. I gradually learn, though, that expressing this musical speech involves a paradox. For if the spirit is to flow into the keys through the conduit of my arm and hand, it has to move in the other direction as well -- from the keys info my arm and soul. Pani Witeszczak's ideal is to make the music sound as if it were playing itself. It is to that end that one has to relax, relax as much as possible -- relax one's arm and one's self, so that one can become the medium through which the music flows as naturally as melting snow in the spring. "Relax," she keeps saying. "All you have to do is let the music be itself." But there is a further twist of the paradox -- for such freedom, such receptivity can be achieved only through the rigor of controlled technique, if I don't ahve to worry about just how I'll execute the next passage, and whether I can manage a jump or a trill. One's fingers can become boneless conduits only if they've been made very strong first. Music may express the deepest truths, but it expresses them through a material medium, and in order to say what I want, I need to bend the physical medium of my arms and fingers to my will. To that end, Pani Witeszczak insists on the virtues of strict, daily discipline. 
...
Music -- philosophers have known its dangers -- inspires me with such grandeur that I think I know what inspiration is about. As I progress to pieces by Mozart or Chopin or Beethoven, I begin to feel in possession of enormous, oceanic passions -- anger and love and joy and grief that surpass merely being angry, or happy, or sad. ... I understand all emotions, no matter how raging or large. If I can express the passions contained within a Beethoven sonata or the Chopin Berceuse, then I know everything about being human. Music is a wholly adequate language of the self -- my self, everyone's self."