Deductum

Deductum is a puzzle game in which you use the rules of logic to prove, step by step, that a conclusion follows from a set of premises. Tutorials introduce proofs and the game’s mechanics, while the problems gradually become more difficult. Every problem has a solution, and you can work them out without guessing.

Problems and sandbox

The game includes 111 problems, including classic theorems such as De Morgan's Laws and the Law of the Excluded Middle. In Sandbox mode, enter any claim using proposition symbols A–H and try to prove it.

Focus on logic

The controls are simple, with no timers or distractions.