Finite game explained

A finite game (sometimes called a founded game[1] or a well-founded game[2]) is a two-player game which is assured to end after a finite number of moves. Finite games may have an infinite number of possibilities or even an unbounded number of moves, so long as they are guaranteed to end in a finite number of turns.[3]

Formal definition

William Zwicker defined a game, G, to be totally finite if it met the following five conditions:[4]

  1. Two players, I and II, move alternately, I going first. Each has complete knowledge of the other's moves.
  2. There is no chance involved.
  3. There are no ties (when a play of G is complete, there is one winner).
  4. Every play ends after finitely many moves.
  5. At any point in a play of G, there are but finitely many legal possibilities for the next move.

Examples

Supergame

A supergame is a variant of the finite game invented by William Zwicker. Zwicker defined a supergame to have the following rules:

"On the first move, I name any totally finite game G (called the subgame). The players then proceed to play G, with II playing the role of I while G is being played. The winner of the play of the subgame is declared to be the winner of the play of the supergame."[4]

Zwicker notes that a supergame satisfies properties 1-4 of a totally finite game, but not property 5. He defines games of this type to be somewhat finite.[4]

Hypergame paradox

A hypergame has the same rules as a super game except that I may name any somewhat finite game on the first move. The hypergame is closely related to the "hypergame paradox" a self-referential, set-theoretic paradox like Russell's paradox and Cantor's paradox.[2]

The hypergame paradox arises from trying to answer the question "Is a hypergame somewhat finite?" The paradox, as Zwicker note, satisfies conditions 1- 4 making it somewhat finite in the same way a supergame was.[2] However, if hypergame is a somewhat finite game, then play can proceed infinitely with both players choosing hypergame as their subgame forever. This infinite would appear to violate property 4, making the hypergame not somewhat finite. Thus, the paradox.[1]

Notes and References

  1. Translating the hypergame paradox: Remarks on the set of founded elements of a relation . Journal of Philosophical Logic . October 1996 . 25 . 5 . 545–557 . 10.1007/BF00257385 . Bernardi . Claudio . d'Agostino . Giovanna . 12745108 .
  2. Web site: Self-Reference . Stanford Encyclopedia of Philosophy . Stanford University . 2 March 2020 . Aug 31, 2017.
  3. Web site: Hypergame . Cornell University . 2 March 2020.
  4. Zwicker . William . Playing Games with Games: The Hypergame Paradox . The American Mathematical Monthly . July 1987 . 94 . 6 . 507–514 . 10.2307/2322840 . Mathematical Association of America. 2322840 .
  5. Web site: Game theory . Encyclopedia Britannica.