This enables the work of holding and moving objects to be distributed easily through the finger, hand and forearm unit. Each part does its share in proportion to its design, no more and no less.

All the movements in the arms are calibrated over the fulcrum of the feet (or sit-bones when seated) in order for the body to remain balanced. This is felt as the body continuously adjusting (often invisibly so) as the arms move over the instrument.

The arms always feel “down” on the instrument; the bow arm is resting down on the strings and the left arm rests down on each note. Gravity requires us to be down if we are to feel comfortable. The experience of “upness”—holding up and lifting in the playing—result in instability and tension.

While we need to work on separate elements in the technique, there has to be a point of integration enabling all parts to work together as one idea, in service of the music. Playing cannot feel like multi-tasking. The Interdependence of the Arms enables us to combine all the motions in the arms in a coordinated and simple way such that the technique serves the music.

Shaping refers to the use of curvilinear motions by the forearm. Benefits of Bow Shaping include: tone production, dynamic control, phrasing, string crossing and bow changes. Benefits of Left Arm Shaping include: creating a smooth and fluid feel to the technique, minimizing other necessary movements, enabling greater speed and comfort.

Grouping refers to creating clusters of notes based on different categories, thereby enabling the brain and body to process them in a simple and organized fashion.

This is the combination of movements that enables the left arm to get to the instrument with ease and comfort. Together, they enable the Finger, Hand and Forearm unit to get to the instrument ready to play and to function in the three-part balance mechanism necessary to hold the instrument.

When we walk, our bodies have to remain fundamentally aligned, both when we move vertically (putting a foot down) and when we move horizontally (swinging over to the next foot). This provides us with the stability to move efficiently and comfortably, with speed and power. The Finger, Hand and Forearm unit have to remain together at all times and in all directions, both in the vertical moment of playing and in the horizontal moving over to the next note. 

The bottom of the string has to make just enough contact with the fingerboard that the string length changes. There is no more pitch after that point. Pitch is a done deal at that point, absolute, finished. (We can feel this easily by using the opposite hand to feel the strings. We instinctively stop at the point of sound. We don’t press or squeeze). When the left arm goes beyond the point of sound, we create tension throughout the arm.

The left forearm can move with ease along four axes; Higher-Lower, In-Out, Rotary and Lateral. While they may seem limited separately, when combined, they allow the arm the full, free range of motion. These four axes work in subtle combinations enabling the forearm to move in the most economical way and to deliver its support to each finger.

We use the Four Axes in combination to map out the shortest route between each note and to find the optimal place for every finger to play in that context.

Forearm rotation is the propulsive movement that sends us from finger to finger with ease, speed and power.

When we change position, the left arm is actually leaping from one place to another. Understanding the laws of leaping enables us to move with security and speed across large and small distances.

When we look at daily life, we realize we hold objects all day without any issues. We are employing a five-finger team, enabling the fingers and hand to gain the support of the forearm by using basic alignment, thereby enabling the hand to hold with ease, comfortably within capacity.

This refers to the left-right motion of the arm. The forearm is the only part of the arm that can initiate movement with ease, and the shoulder simply follows in perfect proportion and synchronization. This is simple to observe in daily life.

A) The string needs to be initiated and then released if it is to vibrate freely. B) The arm has both vertical and horizontal motions. The vertical moment creates the horizontal, just like walking: we take a step, the body goes down and then frees up to move across and over to the next step. The vertical is the engine. Each note is the same: the small vertical motion in the arm frees up and allows the bow to travel to the next note, enabling the arm to move with total freedom.

The bow arm can move into the fingerboard area and towards the bridge—this is the same movement as opening and closing a drawer. In early stages, this movement controls bow straightness. In advanced playing, the same motion works in combination with Bow Shaping to produce color and nuance.