Rules are the Persistent Identity of a Game Across Culture and Context

There are at least two senses in which the RULES schemas offer a "formal" way of looking at games. First, the term formal is used in the sense of "form": rules constitute the inner form or organization of games. In other words, rules are the inner, essential structures that constitute the real-world objects known as games. For example, consider two games of Go that differ in a variety of ways. They might differ in terms of:

• Material: one version is played with stones on a wooden board; the other is played on a computer.
• Motivation: in one a friend teaches the game to a friend; in the other, two masters compete for a prize.
• Outcome: in one game white wins easily; the other game is a very close match with black pulling ahead at the end.
• Time and space: one game is played in ancient China; the other is played in contemporary France.

The list could go on. The point is that although these games of Go would be radically different as game play experiences, all would be identified as the game of "Go." Despite their differences, the games share one thing in common: the rules of Go. These "rules of play" unite all of the games of Go that have ever been or will ever be played. It is in this sense that the rules of Go constitute the formal identity of the game of Go.

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Formally speaking, as long as a deck of cards has the proper mathematical qualities, it can be used to play Poker. In fact, as long as the game "cards" have the right kind of 4 x 13 information and can be randomized (shuffled), distributed (dealt), and properly kept hidden when necessary (in a hand), they would not have to be cards at all. They could be, for example, carefully marked Popsicle sticks. It would be possible to play a game of "Poker" that would not resemble Poker on the surface, and might not be recognized as Poker by observers, but would still possess the formal structure of Poker.

How is this possible? When we talk about the rules of a game— the formal identity of a game—we are not referring to aesthetic qualities (such as the names of the suits) or representational identity (such as its ability to be recognized by an observer). We are limiting the focus to the set of rules, or formal structures that constitute the game. Looking purely at the rules of a game means repressing many other fascinating qualities of game play and game culture.