There’s chess theory, which is rule based and what you start off describing. But then you admit you don’t work directly with chess theory when selecting moves,

There’s chess theory, which is rule based and what you start off describing. But then you admit you don’t work directly with chess theory when selecting moves, there’s a trained black box evaluator that selects candidate moves, which you then select from via chess theory. That’s how you’re finding chess moves in the blink of an eye: you run a fuzzy approximation, then refine the results using higher level reasoning. But you don’t have access to the network doing the evaluation and can’t describe exactly how it operates, just that it was trained on chess theory. It’s that fuzzy reasoning to speed up the process of actually finding solutions that I was calling out as the source of the unknowns in our processing — and at least from my exposure to board games (and their players), it’s often the source of things like innovative moves.