If energy can neither be created nor destroyed.......

The purpose of energy is to allow everything in this 3 dimensional plane to exist. Why it exists I don't know, but I sure reckon there is a REASON, and a good one at that. Personally I think it has something to do with working toward equilibrium, we are supposed to figure that balance is the only way anything can be sustainable - neither excess nor deficit - just sufficient is the answer. Not many get even close to understanding this throughout thier entire lifetime.