Let me illustrate what happens with a image that might be easier to grasp. Imagine your car won’t start and you have to push it. You push forwards with your hands and arms to overcome the resistance of the inertia of the car. While pushing forwards you will experience backwards reactions which flow through your body downwards until they meet and are counteracted by the solid ground under your feet. So your actions are channelled in one direction and the reactions travel in the opposite direction. The power of these equal and opposite reactions can be seen very clearly if you are trying to push your car on an icy or slippy surface.The car will not move but the reactions to your pushing will cause your feet to slip on the ice and actually slide backwards in the opposite direction to your pushing. The exact same thing will happen in piano playing if the reactions are not grounded in a solid basis. The actions of the hands and fingers will cause the rest of the playing mechanism to be displaced backwards and upwards and all the power exerted by the hands and fingers will be wasted in reactions, resulting in a greater or lesser - and in some cases total - loss of power and control. With the Fundamental Action, the reactions are grounded in the torso at the shoulder joint and every unit of force generated by the fingers and hands is transferred directly into key depression. This produces not only maximum power but, equally importantly, total control over the force applied to the key, which translates into total tone control. The necessity for tone control is about the only point upon which all major writers on piano technique are agreed.

There are two ways in which to contain or absorb the reactions caused by finger and hand actions, thus providing the hands and fingers with a stable basis to act against. These correspond to the two ways of playing mentioned earlier. The wrong way uses downward pressure from the forearm; the correct way uses the power and control of the upper arm directing the hands and fingers through the whole arm acting as one unit (the Whole-Arm Action). The correct way will be discussed in the following section; here we will look at the more common, incorrect coordination. This wrong way of playing uses vertical forearm pressure to back up the activity of the fingers and hands, together with stiffening of the wrist and elbow joints. When a note is played by the fingers, the hand presses downwards either to depress the keys itself or to back up the downwards action of the fingers. This downwards movement of the hand then has to be backed up by a downwards movement - or at least pressure - of the forearm. This creates two problems: the forearm either tries to back up the action of the fingers and hands, which it does not have the power to do because it cannot provide a sufficient level of continuous solid basis for the fingers and hands to act against ; or it will try to hit the keys itself, which will result in inaccuracy. In either case, the forearm's constant pushing down into the keys greatly restricts lateral movement, the arms feel unwieldy, the keys seem terribly heavy and the fingers seem to get stuck in the keys - a malcoordination usually referred to as key-bedding, but the cause of which is rarely understood. Also cramp will occur in the forearm as the muscles which operate the fingers are being overworked. The reason why they are being overworked is because without a solid basis against which to act, they cannot act as levers, and without the exponential increase in power accorded by the Law of the Lever the fingers do not have the strength to play what is required for any length of time at the required speed. This technique will work for slow speeds but as a coordination for the bulk of piano playing it is useless. At slow speeds this doesn't matter; playing one note per second, one can use the forearm as basis or use nothing at all and allow the hand to be displaced as there will be enough time to move it back again for the next note. But when it comes to playing 12 or 16 consecutive notes per second, or playing loud, fast, repeated five-note chords it is a different matter. This requires a constant solid basis for every finger to act against. The more stable the basis, the more power will reach the keys for the same amount of finger exertion. Downwards pressure of the forearm cannot provide a constant source of stabilization because the forearm continually needs to move around the keyboard to place the hands in position to play. Also the forearm simply cannot provide a sufficient amount of stabilisation for loud, fast playing. And what happens in practice is that instead of providing a basis for the action of the fingers and hands, the forearm gets involved in the actual tone-producing action itself. The over-exertion of the fingers without a solid base to act against leads to tension and cramp in the forearm, coupled with loss of power, tone and key control. This is the greatest single cause of failure to achieve a reasonable standard of piano performance.