Koster talks about how games all teach us something, whether that something is a skill applicable to modern life or an obsolete skill that once was necessary to learn. Pac-Man at first seems to be about map exploration, but I think it also teaches us how to predict the future within the confines of spatial reasoning. There are clear demarcations of which players go where and at what speed. Anticipation and map awareness are the only way to win, but after a couple games, it’s easy to get bored of Pac-Man. As adults, we’ve already mastered this skill set, but most children have not, which is why they are fascinated by other predictive spatial reasoning kinds of games, such as Battleship or Tetris.
Pac-Man also has a hierarchy of power. At any time, you know if Pac-Man can eat the Ghosts or if the Ghosts will eat Pac-Man, who is the chased and who is the chaser.
Flow is a different beast entirely. Pac-Man has a clear goal, but Flow is unstructured play or paidia as Callois calls it. It doesn’t seem to teach us anything. There is no map exploration goal, no spatial reasoning to figure out. Instead, it seems to cross over into pure art. It is beautiful and you can play it, but not in the definitions either Callois or Koster provided. However, art is meant to be evocative in one way or another and Flow is evocative in that there are no clear rules or expectations of the gameplay.