The great pianist, Josef Hofmann, imparted words of wisdom when he answered the following question posed by a student that related to the thumb and piano technique:
“What is the matter with my scales? I cannot play them without a perceptible jerk when I use my thumb. How can I overcome the unevenness?”
The questioner expressed a universal concern among pianists regardless of proficiency. And it’s because the thumb is so unique. The shortest of five fingers, it has a tendency to be played prematurely and with a conspicuous accent when it passes under longer fingers in the course of a scale, arpeggio, or in any passage where it shifts.
Hofmann had responded with a similar opinion:
“The thumb usually waits until the very moment when it is needed and then quickly jumps upon the proper key, instead of moving toward it as soon as the last key it touched can be released. This belatedness causes a jerky motion to the arm and imparts it to the hand.”
In the video I produced on this very subject, I demonstrated ways to avoid the “belatedness” and “jerkiness” that Hofmann had referenced.
My discussion and demonstration focused on what I termed the “pocket” thumb and “swishy” thumb.
The “pocket” concept involves “preparation” for the shift under other fingers. The “swishy” adjective pertains to relaxing the rotating thumb when in motion and its making a soft, unobtrusive landing. Even when playing FORTE or loud, I believe the thumb should be relaxed, cushioned, if not underplayed.
If you have your own ideas about the thumb and the art of piano playing, please share them.
The pianist speaks: “I use a rotational movement with the thumb.” [Demonstrating for the author, Arrau makes his rubber-jointed right thumb crawl like a caterpillar from a white key to a black; the top joint ascends first while the bottom joint maintains contact with the white key.]
Another relevant point made by Arrau: “It is important never to feel the actions of the fingers as independent from the arm.”
Arrau thinks of “ten agile, individually weighted fingers, attached to rotating wrists. He says convincingly, that the pianist has to “develop a feeling for the arm as a unity, not divided into hand, wrist, forearm, elbow.”