Tarati
A downloadable board game for Windows, macOS, Linux, and Android
Tarati is a minimalist abstract strategy game created by George Spencer-Brown, the mathematician and author of Laws of Form. It applies his calculus of distinctions to the board: a game that is simple to learn yet deep in consequence.
▶ Play Online for Free
https://tarati.tech — no installation required. Online matchmaking, ranked games, tournaments and live spectating, right in your browser.
What is Tarati?
Designed as a practical application of Spencer-Brown's distinction calculus, Tarati embodies the mathematical and philosophical principles of Laws of Form.
Two players move pieces across a board of 23 vertices, flipping the opponent's pieces to their own color and promoting their own — all governed by a handful of elegant rules.
How to Play
- Goal: capture the opponent's last piece in a single move (Mit), or leave them with no legal moves (Stalemit).
- Cob: the basic piece — moves forward, toward the opponent's side.
- Rok: an upgraded Cob that moves freely in any direction.
- Capture: when a piece arrives at a vertex, it flips every eligible enemy piece connected to it — but only those it approaches from outside.
The pre-adjacency rule — you must approach from outside — is the heart of the game's tactics.
Features
- 🤖 AI engine with four difficulty levels (Minimax + Alpha-Beta pruning)
- 🌐 Online multiplayer — matchmaking, Glicko-2 rating, leaderboards, profiles, follows, challenges, spectating and tournaments
- ⏱️ Five time controls — Unlimited, Sudden Death, Fischer, Bronstein, Byoyomi
- 🎨 Swappable color palettes and customizable piece sets
- 📖 Interactive tutorial and a full game library with move-by-move replay
- 🌍 Bilingual — English and Spanish
- 👤 Guest access — play online without registering
Available Everywhere
- Web — play instantly at https://tarati.tech
- Android — on Google Play
- Desktop — Windows, macOS and Linux
About
Tarati is an educational implementation built to make Laws of Form accessible through play. The source code is released under the MIT License; the original game concept and Laws of Form belong to George Spencer-Brown.
"To teach pride in knowledge is to put up an effective barrier against any advance upon what is already known." — George Spencer-Brown
Download
Install instructions
No download needed? You can play instantly in your browser at https://tarati.tech.
🪟 Windows (.msi)
Double-click the .msi and follow the installer. If Windows shows "Windows protected your PC", click More info → Run anyway — this appears because the installer is not code-signed.
🍎 macOS (.dmg)
Open the .dmg and drag Tarati to Applications. The first time you launch it, macOS may say it "cannot be opened because Apple cannot check it for malicious software". Right-click (or Control-click) the app → Open → Open to confirm. You only need to do this once.
🐧 Linux (.deb)
Install with your package manager or run sudo dpkg -i tarati_*.deb. Everything needed to run the app is bundled — no separate Java runtime required.
🤖 Android (.apk)
Download the .apk and open it. Android will ask permission to install from this source — allow it under Settings → Install unknown apps. For automatic updates, prefer the Google Play (https://play.google.com/store/apps/details?id=com.agustin.tarati) version.
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