About Tarati
Tarati is an abstract strategy board game created by George Spencer-Brown (1923–2016), the British mathematician best known for Laws of Form (1969). The game is a practical application of the ideas in that book: a calculus built entirely on the single act of drawing a distinction.
Laws of Form and the game
Laws of Form develops a complete logical system from one primitive operation — the distinction, the drawing of a boundary that separates inside from outside. Tarati turns that idea into play: pieces cross boundaries between the board's concentric zones, and capturing works by flipping an enemy piece to your side — a change of the mark it carries, a re-drawn distinction.
The game's central tactic, the pre-adjacency rule (you may only capture a piece you approach from outside), is itself a statement about boundaries: a distinction only takes effect when it is crossed from without.
This implementation
Tarati is a free, multiplatform implementation built with Kotlin Multiplatform and Compose: one shared codebase running on the Web, Android, Windows, macOS and Linux. It offers online multiplayer with Glicko-2 ranking, four AI difficulty levels, chess-style position analysis, an interactive tutorial, and a separate 2–6 player variant, Tarati Six.
It is an educational project. The source code is released under the MIT License; all rights to the original game concept and to Laws of Form belong to George Spencer-Brown.