The difference between white key and black key sonority on the piano is striking to a child. It is perhaps one of the reasons why children balk at reading music in the flat keys. I decided to test that proposition the other day by having a child read and react to, one sound at a time, a Haydn minuet in E-flat.

Her responses to the specific voicing of intervals, position of black in relation to white keys, registral placement on the piano -- all revealed extremely vivid ear-pure response.

I asked her if the sounds bothered her when she heard me play. "No," she replied, "because you know what is coming next."

Incidentally, the strategy was to begin not at the beginning but at a cadence. Reading "backward" from the cadence -- i.e., approaching it from increasing distances -- clarified a context in which all kinds of dissonance became meaningful. She ended up playing the whole thing at first sitting, by her choice, though it was not at all a simple piece.

I take this as a clear demonstration of why I do not teach major keys as if they are interchangeable: they are not!