Beats, measures and bar lines all look so innocent. All you need to do is figure out the arithmetic and then count, count, count!

It works until you start to react to actual sounds.

The other evening I heard Marc Ponthus play Schumann's Kreisleriana with breathtaking intensity: at times faster than fast (as specified by the composer), at times surpassing slow (also specified). It was a beautiful lesson in the fantasy life of tone.

Even children and people with limited physical capability have access to that level of insight, power, and satisfaction.