Depending on the variation, it is held that the whole world, or all those who are aware of the game, are playing it at all times(from the wikipedia article)
So either everyone in the world is playing or only the people that know the game are playing
Minor correction, the Wikipedia article says it is alternatively expressed as - meaning that the expanded definiton which is “Everybody in the world who knows about The Game is playing The Game”, implies the first definition is that you have to know before you play.
Depending on the variation, it is held that the whole world, or all those who are aware of the game, are playing it at all times(from the wikipedia article)
So either everyone in the world is playing or only the people that know the game are playing
Minor correction, the Wikipedia article says it is alternatively expressed as - meaning that the expanded definiton which is “Everybody in the world who knows about The Game is playing The Game”, implies the first definition is that you have to know before you play.