Living bodies not only have a biological equilibrium toward which they grow and which they maintain, they also take active steps to prevent the environment from interfering with this.
This has two aspects to it: First of all, living bodies tend to rebuild parts that have been destroyed by outside energy (or inside wear and tear, for that matter), insofar as they have the mechanisms to do so.
This is fairly straightforward, given that the unifying energy builds the body in the first place, and gives it its super-high biological equilibrium. It would not be surprising to find that one of the things done by nutrition in maintaining the equilibrium would be to keep the body's parts intact in the face of energy that would tend to break them apart or destroy them. This is all the more necessary once it is realized that the living body is very complex, and hence in itself more delicate than simple bodies need to be.
Living bodies are, of course, very tough in practice; and they are actively tough, not just passively so. Energy or foreign objects that they don't "want" entering them are attacked very aggressively, and the body is quickly brought back to where it was before, for practical purposes--though the scene of the battle might be marked with a scar.
This again shows a degree of control over itself that the inanimate body does not have; if an inanimate body is acted on by energy that it can absorb, it will absorb it, even if this energy will destroy it. Living bodies tend to absorb energy if they need it and reject it if they don't. And this ability to seek wanted energy and avoid it when it is unwanted becomes more pronounced the higher one goes in the scale of life. One of the main differences between plants and animals is precisely this: that animals can sense danger and move to avoid it, and can sense their own needs and what satisfies them, and move to acquire the proper food.
In this respect, living bodies seem to have taken the internal elasticity of inanimate bodies (which allows them to return to their ground state with only an accidental change) and raised it to a higher level; living bodies seem to be able to turn the tables on their environments, making what should be destructive useful. Oxygen, for instance, is corrosive, and destroys inanimate bodies by rust and burning; but living bodies utilize this destructive chemical precisely to stay alive, by controlling the fire and making it break down the food. The same goes, of course, for the hydrochloric acid in our stomachs.Next