I'll play. Here's my stab in plain English.
Aiki is a demonstrable body skill and mental state achieved through the neutralization of opposing forces, and the directing of power via the center/will through intent/mind.
Cool! Thanks, Dan! Much appreciated. Just for clarification's sake, are you saying aiki can be one and/or the other (body skill; state of mind)? Or is aiki only both at the same time?