E.g. “does this plan avoid having a steganographically encoded world-ending message hidden in it” is more co-NPish than NP-ish. Like, just showing me the plan doesn’t make it easy to verify that there isn’t a hidden message, even if there isn’t a hidden message. Checking whether a sequence of actions is the first half of a strategy to take over the world is potentially more like P-space.
E.g. “does this plan avoid having a steganographically encoded world-ending message hidden in it” is more co-NPish than NP-ish. Like, just showing me the plan doesn’t make it easy to verify that there isn’t a hidden message, even if there isn’t a hidden message. Checking whether a sequence of actions is the first half of a strategy to take over the world is potentially more like P-space.