Quod Erat Demonstrandum
Cheapest right now: $2.63 USD at Steam (12% off). 1 store compared, checked 13 Nov 2026.
Discover the challenging fun of validating logical proofs, beginning with simple propositional calculus and ending with complex, multi-domain predicate calculus. Prove yourself to be a master of logical thinking!
Genres: Casual, Indie, Strategy
Platforms: Windows, Linux
| Store | Price | Discount |
|---|---|---|
| Steam | $2.63 | 12% |
Is it a good deal right now?
$2.63 USD at Steam is 12% off. We have no record low for Quod Erat Demonstrandum to compare it with. The regular price is $2.99, so $2.63 saves $0.36. The Steam discount ends on 19 November 2026 at 18:00 UTC.
Price history
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Screenshots
System requirements
Windows
Minimum
- Requires a 64-bit processor and operating system
- OS: Windows 10
- Processor: 1.6 GHz dual-core
- Memory: 4 GB RAM
- Graphics: Integrated graphics
- DirectX: Version 11
- Storage: 500 MB available space
- Sound Card: Any
Recommended
- Requires a 64-bit processor and operating system
- OS: Windows 10
- Processor: 2.0 GHz dual-core
- Memory: 4 GB RAM
- Graphics: Integrated graphics
- DirectX: Version 11
- Storage: 500 MB available space
- Sound Card: Any
Linux
Minimum
- OS: Ubuntu 20.04+ / SteamOS 3.0
- Processor: 1.6 GHz dual-core
- Memory: 4 GB RAM
- Graphics: Integrated graphics
- Storage: 500 MB available space
- Sound Card: Any
Recommended
- OS: Ubuntu 22.04+ / SteamOS 3.0
- Processor: 2.0 GHz dual-core
- Memory: 4 GB RAM
- Graphics: Integrated graphics
- Storage: 500 MB available space
- Sound Card: Any
As listed on the game's Steam page.
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