Notes from a Medium-Sized Island

Still sad that SAC seems to end up being as complicated as it is. Surely there's some deeper duality between observe-and-do-depth-first-search-to-compute-stuff-terminating-when-you-reach-cached-answers and change-and-do-something-like-depth-first-search-terminating-when-you-stop-making-changes that can be exploited?