In the past few days, I have been doing a lot of thinking about the ontology of interactive systems, and part of that has been concerned with ambiguous decision making. In the interest of not being insulated too much inside my head, I thought it might be worthwhile to create a thread for discussing its finer details. We've had some discussions about it before, but as far as I can recall, we've never really had an in-depth discussion concerning what precisely decision making entails (except maybe here and here, but neither thread yielded much conversation). Necessary and sufficient conditions and logical implications and all that. Here's how I understand it at the present moment: Ambiguous decisions: Require an agent to select one of two or more options. Yield irreversible consequences with respect to achieving an unambiguously defined goal. Are made under circumstances in which the agent's certainty with respect to the consequences is greater than 0% and less than 100%. Some consequences of this definition: Ambiguous decision making implies the existence of both win conditions and loss conditions. That is, ambiguous decision making can only occur in a contest. There is no such thing as a toy or a puzzle that involves ambiguous decision making. Games are a proper subset of contests. Ambiguous decision making implies that a true game-end value hierarchy cannot exist. That is, 2nd place, 3rd place, and so on do not reliably and accurately measure the quality of ambiguous decision making beyond a binary success/failure. We discussed this here. As a consequence of point 3, deterministic systems of perfect information (e.g. Chess, Go, Othello, Tic-Tac-Toe, etc.) are games only insofar as the agent is not aware of a solution*. If a solution is known, the certainty referred to in point 3 is at 100%, and therefore the "decisions" made are not ambiguous at all. As games are defined as being contests of ambiguous decision making, any contest involving only "decisions" in which agents simply perform the actions already known to be the correct moves for achieving the win conditions is not a game. Therefore, at least in the context of deterministic games of perfect information, ambiguous decision making (and therefore also deterministic perfect information games) constitutively depends upon more than the details of the system. It depends also upon characteristics of the agent, specifically the agent having incomplete knowledge of the game's decision tree lacking the knowledge of a move that guarantees a win lacking the knowledge of a perfect set of optimal moves. Does anyone disagree with any of the above or agree but have something to add to it? Is there a way that the above could be worded better? Is there something I forgot? Any glaring errors that I have overlooked? Anyone agree with any of the above consequences and care to suggest a formal proof thereof? One point I am presently very unsure of is the implications of chance and imperfect information on the third consequence. When outcomes are uncertain as a result of randomness or hidden information rather than on just a limited knowledge of the decision tree, we often (or always?) get risk management scenarios rather than just pure tactical decisions. When this is true, is the level of certainty in point 3 always less than 100%? You could theoretically be 100% certain about the probabilities of the possible outcomes. Does this necessarily generate an optimal move, and if so, then does this render the decision-making non-ambiguous? * There is an avenue of thought in which I qualify this statement, but I think at the present moment it's beyond the scope of this thread since it has more to do with general ontology than with decision making specifically. I will be exploring this avenue separately.