I'm wondering what is more fundamental to the concept of something changing, force or energy. As I see it, energy is the capacity of a system to do work. Also if we don't have energy in the universe, there is no physical universe for us to experience. Must be pretty fundamental. On the other hand if I separate the notion of 'what' changes from 'the process of change' it seems force is a bit more fundamental. Force is the space derivative of energy. An object at rest stays at rest unless a force is acted upon it. Just curious your thoughts?