Agency
If you stop to think about it, the fact that we can do something, and that thing can have an impact on the people around us, can seem quite wondrous. Add to that the fact that sometimes your actions will have a great impact, and at other times the exact same action may change very little, and you’ll begin to approach an important mystery in animist thought. Melanesians and Polynesians talk about mana. Ongweoweh talk about orenda. Algonquian peoples talk about manitou. In English, we might not have any word that gets as close to the concept as “agency.”
At all times during the game, you can say what your character says and does, but sometimes that will make a difference, and sometimes it won’t.
For example, our story might stray out to other places than the ones that people have chosen to play, but those places have no agency in our story. The things that happen there might fill in small details, but the story won’t progress much until it comes back to one of the places that someone at the table plays.
When the story comes to the place that you play, your human character loses agency as hen becomes part of the place. When hen goes to places played by other players, hen will gain agency, as the contrast between the place hen has a connection to and the place that hen has gone creates the potential for significant change.
Certain game mechanics exist to mark the progression of the story. When your character does something in the story but no one engages those mechanics, compared to those times when your character does the exact same thing but someone does engage those mechanics, that highlights these mysteries of agency.