Eleusis is a shedding-type card game where one player chooses a secret rule to determine which cards can be played on top of others, and the other players attempt to determine the rule using inductive logic.

The game was invented by Robert Abbott in 1956, and was first published by Martin Gardner in his Mathematical Games column in Scientific American magazine in June 1959. A revised version appeared in Gardner's July 1977 column.

Eleusis is sometimes considered an analogy to the problems of scientific method. It can be compared with the card game Mao, which also has secret rules that can be learned inductively. The games of Penultima and commercially produced Zendo also feature players attempting to discover inductively a secret rule or rules thought of by a "Master" or "spectators" who declare plays legal or illegal on the basis of the rules.

Rules

The game is played by creating a row of cards in sequence. At the start of the game the dealer (known as "God") invents a secret constraint for how these cards must progress: for example, "each card played must be higher than the last, unless the last card was a face card, in which case any numeral card may be played".

Two decks of cards are shuffled and 14 cards dealt to each player except the dealer. One card is dealt face-up to start the row and a random player chosen to start.

On a player's turn they must add one or more cards from their hand to the row, in sequence. The dealer judges this play: if the entire play fits the dealer's rule, the cards are left in place as part of the row. Otherwise, they are removed from the row and "sidelined", as to be put below the card that they attempted to follow, and the player is dealt a number of penalty cards equal to twice the number of cards they attempted to play that turn.

Abbott himself considered the variant a "great game", and referred to it as "Eleusis Express".

References

  • Robert Abbott's website page about Eleusis and Eleusis Express
  • An online implementation of the game (both single and multi-player) on the Telegram chat platform.