The companion game
The Expedition
An expedition across the argument of the book. Each stage of the series is a land, and you cross it by earning what that stage earns: no tool may be used before the land that earns it.
How it is played
Every land is a logic puzzle. Its steps are claims in the book's register, and its traps are the inferences the book rules out. Each lesson starts from a familiar scene whose logic matches the claim, such as a wheat field seen through a camera or the two ends of a stick.
Origin. At the gate, set down the compass, clock, ruler, map and name tag; each returns in the land that earns it. Then peel away place, things, organization and persistence until only “no operative distinction” can be reported.
Difference. Find the least structure beyond Origin: two marks and one undirected tie, told apart only by the tie, with nothing changed when their labels swap.
New lands open here as each becomes playable.