Logic Puzzles

Logic puzzles inspired by the books of Raymond M. Smullyan.

The Island of Knights and Knaves

Who is a knight and who is a knave? Adapted from puzzles by Raymond M. Smullyan, particularly those found in What is the Name of this Book?.

The Isle of Dreams

Are islanders nocturnal or diurnal? Are they awake or asleep? Inspired by puzzles from The Lady or the Tiger?.

Portia's Caskets

Can you find Portia's portrait? Adapted from puzzles found in What is the Name of this Book?.


The Forest of Forgetfulness

With liars like the Lion and the Unicorn, how can Alice know what day it is? Inspired by puzzles from What is the Name of this Book?.

The Fickle Sentries

If you can see through the statements made by these unreliable guards, the treasure is yours! Based on similar puzzles by Raymond M. Smullyan.

Inspector Craig

Only logic can uncover which suspects are guilty. Based on case files found in What is the Name of this Book?.


Tiger or Treasure?

Choose between two doors which may lead to treasure, or something less pleasant. Adapted from puzzles in Smullyan's The Lady or the Tiger?.

Tweedledee and Tweedledum

Who is lying, and which brother is which? Inspired by puzzles in Alice In Puzzleland.

Subterranea

Day-Knights and Night-Knights! Inspired by puzzles in To Mock a Mockingbird.