Yeah, I think an important part of games is "imperfect information" which makes the outcome uncertain. Like the use of dice in RPGs or not knowing the other player's hand in card games. Without uncertainty, it's at best an exercise in following instructions.
Viewing post in what makes a solo LARP a game?
Yeah... probably any definition is going to fall down at some point, >_<.
Granted, Chess's imperfect information is related to the number of potential moves and directions a match can take from any given point going forward, and not knowing what the opponent will take, as opposed to 'hidden' information like cards in a player's hand.
But, I realized after posting that definition wasn't going to hold up in all cases. ^_^;
I think there's a point where a thing isn't a game... like an artificial heart isn't a game, for sure, but that doesn't mean there's an easy-to-agree-upon border between game and non-game. {shrug}