Eleusis (card game)

Eleusis is a card game designed by Robert Abbott, meant to simulate scientific discovery. It is a game of inductive reasoning where one player, the Dealer (also called the Scientist or Lawgiver), secretly invents a rule determining the order in which cards can be played. The other players, called Researchers, try to discover this rule by playing cards and observing whether they are accepted or rejected by the Dealer.

Gameplay:

One player is designated the Dealer and creates a secret rule (often called "The Law") governing the sequence in which cards can be played. This rule can be simple (e.g., "alternate red and black cards") or complex (e.g., involving the value of the previous card and the suit of the current card). The other players are Researchers. The Dealer deals a hand of cards to each Researcher and starts a "play line" with one or more cards.

Researchers take turns playing cards from their hand onto the play line. The Dealer announces whether the played card "follows the Law" or not. A card that follows the Law is added to the end of the play line. A card that does not follow the Law is placed in a side row belonging to the Researcher who played it. The side row indicates an incorrect guess and provides data for the player to refine their hypothesis.

Researchers can make a hypothesis about the Law at any time. If the hypothesis is correct, the Researcher becomes a Dealer in the next round. If the hypothesis is incorrect, the Researcher must draw penalty cards. The game continues with Researchers playing cards and refining their hypotheses until someone correctly guesses the Law.

Goal:

The goal of Eleusis is to be the first player to correctly guess the Dealer's secret Law.

Variations:

Several variations of Eleusis exist, often involving more complex Laws, different scoring systems, and the introduction of "prophet" cards that allow players to test a card without penalty. Some variations also introduce mechanisms to make the Dealer’s rule less opaque, such as allowing limited questions about the validity of certain card sequences.

Educational Value:

Eleusis is often used as an educational tool to teach scientific reasoning, hypothesis testing, and inductive logic. It encourages players to formulate hypotheses, test them against data, and revise their theories based on the results. It highlights the process of scientific discovery and the importance of experimentation in understanding complex systems.