Balance is the first axiom of classical ballet. All positions at all times use balance as the highest principle. But this is not necessarily because of anything other then balance is how we survive, dancing or not. If you want to believe that the dynamic principle of existence is to “survive!” then balance is the dynamic principle of “survive“!  All movements of any kind from lifting a soup spoon to the lips to moving a 100 pound weight requires a process of balance and leverage. Anchored in your seat, your arms and hands are then free to leverage up a cup of coffee, etc, …, etc…. ad infinitum.  The only respite from this ‘balance’ commands seems to be during sleep. I believe that the need for sleep is also a need to turn off our top most sense of ‘must stay on balance’ at all times command.