Just as nature abhors a vacuum, so do our minds fill music's sensory void with metaphor. But music can at least be high or low, can't it? No, because that too is a metaphor. The relative "height" of a note depends on the frequency of its vibration, and has nothing to do with its situation in space.
Moreover, this high-low notion, when expressed in terms of a keyboard, brings in its train another idea to which we are just as firmly wedded. Low-to-high means left-to-right: while the left hand growls, the right hand sings. Well, surely that goes without saying!
Oh no it doesn't. And to prove it is a man with a piano whose keyboard ascends from right to left. Chris Seed is a left-hander, and he's just created the world's first left-handed piano, out of sheer frustration. "At the Royal College of Music my tutors were always saying `If only your right hand were as good as your left.' My right was clumsier, which meant I had to shy off Chopin and the Romantics - the music I most wanted to play."
Two years ago he tried a computerised keyboard in a mirror image of the normal pattern. He found he adjusted to it remarkably quickly, so decided to commission the building of a real-life instrument - a replica of an 1826 Graf fortepiano - along similar lines. "People told me I was mad, but I knew it was a good idea."
Just how good an idea it was emerged recently when he took his Graf to a period-instrument fair in Bruges, where left-handers fell on it with delight. He noted that Oriental players were particularly adept at it, right-handers as well as left. "Maybe it's because they're already used to making this kind of adjustment, having to read at home in the opposite direction."
Making the change, he says, has fundamentally altered his perception of certain pieces of music, a discovery that may have interesting implications for right-brain/left-brain research. Meanwhile, psychologists at the Royal Holloway College are devising a project - based on Seed and his seedlings - to examine the way that old habits affect our acquisition of new skills, and also the way these new skills may in turn affect the old habits.
There is a celebrated ocular precedent for what Seed is doing. What we see is printed upside-down on the retina,but our brains interpret it as the right way up. When people are experimentally given glasses that automatically invert the image, they spend three days in ocular confusion before their brain can readjust. When the glasses are taken off, they stumble about again until their brain reverts to the original adjustment.
It took Seed two weeks to make his initial adjustment, and when he plays a conventional instrument he must consciously switch modes, but he now plays as comfortably in both directions. But he is not a typical case, whereas I most certainly am, and when I try to pick out a simple tune on the Graf I feel as though I'm going mad. After a few minutes I discover it's easier with my eyes shut, but the thing still seems deeply weird.
Seed laughs: his eight-year-old son, who is also a left-hander, apparently plays in both directions, as do his left-handed pupils at Winchester College where he teaches one day a week. Will this invention make him rich? "I doubt it. I looked into the patent situation, but was told I couldn't own rights because the thing has no new parts. I'm just the pilot for an idea."
On the other hand, he has patented a simple midi adaptor (available from Loughborough Projects, 01509 262 042) which will invert any electronic keyboard. This, I guess, could be a morale-booster for young left-handers. Next Thursday he will give a recital on his Graf at London's Queen Elizabeth Hall - Mozart, Beethoven, Schubert and Chopin. This will be a triple coming- out - for the left-handed concept, for the rare Graf replica, and for himself as a pianist. Yes, he admits, the evening will have a lot riding on it.
Queen Elizabeth Hall box office 0171-960 4242