Mornington Nomic

Version 6 (March 2019)


Mornington Nomic is a game set on the London Underground, where the rules are made by the players as they are playing.

Mornington Nomic is a Nomic game, inspired by the improvisation game “Mornington Crescent” from I’m sorry I Haven’t a Clue.

The rules are presented in 2 sections: core rules, which provide rules for changing the rules, and the game rules, which are the rules about how the game is played. At least one player should know the core rules, but every player should know the game rules before beginning play.

PDF versions: full colour or black and white.

What you need

In order to play Mornington Nomic, you’ll need:

Core Rules

Core rules make explicit many details about rule changing, and thus are harder to change than the Game Rules.

  1. All players must always follow all the rules that are in effect. The rules in this booklet are in effect when a game begins.

  2. A rule-change is the addition, removal, or amendment of a rule.

  3. Every player is an eligible voter. Every eligible voter must participate in every vote on rule-changes.

  4. A rule-change that changes a Core Rule requires a unanimous vote. (Rules 101-110 are core rules).

  5. All proposed rule-changes shall be written down before they are voted on. If they are adopted, they shall guide play in the form in which they were voted on.

  6. An adopted rule-change takes full effect at the moment of the completion of the vote that adopted it. No rule-change may take effect earlier, even if its wording explicitly states otherwise.

  7. For convenience, each proposed rule-change shall be given a number, regardless of whether it is adopted. The numbers shall begin with 301, and each rule-change proposed in the proper way shall receive the next successive integer.
    If a rule is amended, it receives the number of the proposal to amend it (and loses its original number).
    If a rule is removed but then added again, it receives the number of the proposal to add it back in (not its original number).

  8. Other players may suggest amendments or argue against a proposal before voting on it. A reasonable time must be allowed for this debate. The proponent decides the final form in which the proposal is to be voted on and also decides the time to end debate and vote.

  9. A player always has the option to forfeit the game rather than continue to play. No penalty worse than losing, in the judgement of the player to incur it, may be imposed.

  10. No player may be eliminated from play, except when the game has concluded.

Game Rules

  1. Players shall take turns in clockwise order. Turns may not be skipped or passed, and parts of turns may not be omitted, unless a rule explicitly says otherwise.
    Players should decide amongst themselves who goes first.

  2. One turn consists of two parts in this order:

    1. proposing one rule-change (and holding a vote on it), and
    2. making a MOVE.
  3. A player makes a MOVE by stating the name of a Tube Station.

  4. The winner is the first player to MOVE to Mornington Crescent.

  5. No player may MOVE to Mornington Crescent.

  6. A rule-change is adopted if and only if there are more votes for the rule than against the rule.

  7. Each player always has exactly one vote.

  8. If two or more rules conflict with one another then the rule with the lowest ordinal number takes precedence.
    If at least one of the rules in conflict explicitly says of itself that it defers to another rule (or type of rule) or takes precedence over another rule (or type of rule), then such provisions shall supersede the numerical method for determining precedence.
    If two or more rules claim to take precedence over one another or to defer to one another, then the numerical method again governs.

  9. If players disagree about the legality of a move or the interpretation or application of a rule, then any player can invoke JUDGEMENT (see next section).

  10. If the rules are changed so that further play is impossible, or if the legality of a move cannot be determined with finality, or if by the Judge’s best reasoning, not overruled, a move appears equally legal and illegal, then the first player unable to complete a turn is the winner.
    This rule takes precedence over every other rule determining the winner.


Note: all of this section is considered to be part of rule 209, and thus can be amended or removed as part of that rule. It is placed here for convenience sake.

If players disagree about the legality of a move or the interpretation or application of a rule, the player preceding the one taking their turn is to be the Judge and decide the question.

When Judgement has been invoked, the next player may not begin their turn without the consent of a majority of the other players.

The Judge’s Judgement may be overruled only by a unanimous vote of the other players taken before the next turn is begun. If a Judge’s Judgement is overruled, then the player preceding the Judge in the playing order becomes the new Judge for the question, and so on, except that no player is to be Judge during their own turn or during the turn of a team-mate.

Unless a Judge is overruled, one Judge settles all questions arising from the game until the next turn is begun, including questions as to their own legitimacy and jurisdiction as Judge.

New Judges are not bound by the decisions of old Judges. New Judges may, however, settle only those questions on which the players currently disagree and that affect the completion of the turn in which Judgement was invoked. All decisions by Judges shall be in accordance with all the rules then in effect; but when the rules are silent, inconsistent, or unclear on the point at issue, then the Judge shall consider game-custom and the spirit of the game before applying other standards.

This game was created by Avery Lychee, and is based on Nomic by Peter Suber, and vaguely inspired by Mornington Crescent.

If you play this game, let me know how it goes – I’m open to changing the initial ruleset if there’s anything unclear or confusing.

It was inspired by a (long dead) online game of Nomic based around Mornington Crescent, which you can find here. Since they didn’t provide their initial ruleset, I rebuilt it. Originally, my rules were just the Nomic rules and 202–204, but after a few playtests, I realised that most of the rules/terminology of Nomic are excessive for a game that’s more about building a board game than playing with the idea of rules.

The content of these rules is licensed under the Creative Commons Attribution 4.0 International License - feel free to share, modify, and re-distribute.

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Version 6 (March 2019)