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What is WaterWorld?

Waterworld is a variant on the ever-popular game Minesweeper, with two differences:

a waterworld screenshot
  • It is played on a triangular grid,
  • It distinguishes between guessing the contents of a location, versus asserting that you know the contents¹

Although the game is fun to play in it's own right, we use it to illustrate how playing the game is really just an application of logic—in particular, inference rules, as explained in TeachLogic's Base module.


WaterWorld runs on top of PLT Scheme (DrScheme), and therefore runs on Windows (95 and up), Mac OS X, or Unix running the X window system.

Download Instructions

  1. Download and install DrScheme if you don't already have it on your computer. (It's a large program² but an easy install.)
  2. Download waterworld.plt, saving it to your disk.
  3. Run DrScheme, and from the File menu, select Install .plt file…, specifying the file you just saved.
  4. You may delete the file ww.plt downloaded in step 2 at your leisure.
  5. Run the game by starting up DrScheme and evaluating the expression (require (lib "waterworld.ss" "waterworld")).
    (You can make a platform-independent launcher by selecting Scheme > Create Executable….)

You are free to browse and edit the source; let us know if you have a contribution!

Game Rules

Synopsis: left-click on a location to indicate that it's safe (water), and right-click (or control-click) to indicate unsafe (pirate). At the same time, holding down the shift key to indicates an assertion, otherwise your move is considered a guess.

There are several possible outcomes to a move; WaterWorld will always continue the game, even though some of those outcomes are mistakes where normally a game would end:

¹ Another slight difference is that in traditional Minesweeper, flagging a location as dangerous has no actual meaning—it is just a note to yourself. This isn't so in Waterworld: when you mark a WaterWorld location as dangerous, you'll lose if it's actually safe.    (back to text)

² Note that installing DrScheme to run Waterworld is a bit like visiting the Louvre just to get a postcard of the Mona Lisa: sure it suffices, but it also provides other opportunities. You can use DrScheme to learn how to program and to write sophisticated programs.    (back to text)

³ Well, remember to watch for corner cases: If you've set the total number of pirates to be zero, then even your first move should be an assertion.    (back to text)

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