I sometimes get the feeling with Bach that it's "complete" music. It's "all there." I'm not sure exactly what I mean by that, maybe in part there there is not one note that is uncertain, maybe that it is music that cannot possibly be surpassed, but it's definitely something I get with a lot of his music, and only his music. It is astonishing to me that this music was created before the Classical and Romantic periods, as it seems to have reached a pinnacle of tonality, at least.