> Leibniz uses "original capacity" here to distinguish primary from secondary causation, noting that "secondary causes operate by virtue of the primary". I take this to mean that if a mover is being moved by something else, its power is only by virtue of the thing moving it, rather than an original capacity. I therefore require that the mover not be moved itself, for the conclusion of this premise to apply.
I find this quite elegant actually. It's like an allowance of energy in a fractal pattern. Feels elegant!
So the argument hinges on the composition of (all) moving objects and the premise that the composed body is also moving but cannot be moved by another body since all the bodies are in the composition.
Supposing the only objects in the universe are two objects moving each other (in a cycle), they are considered a single body moved by an immaterial body because their composition cannot move itself? So everything boils down to where does energy come from?
Think of it as a budget of initial size.
So the bodies are limited as a whole vs the incorporeal which is infinite and influences the bodies total energy distribution per allowance.
P3 Infinite power is an original capacity to move the infinite.
So anything moving anything has infinite power, in which case everything moving something has infinite power?
LE: I re-read the P3 premise: only movers that aren't moved themselves have infinite power. All movers that have bodies are moved themselves (P6), so they don't have infinite power.