Syllogica

Each round gives you premises and a set of candidate conclusions. Assemble the Venn-region tiles that model the premises, then judge which conclusion the diagram actually supports. The trap is the fallacies, conclusions that sound right but break down on the regions, like an undistributed middle or an illicit conversion. Build the picture and let it decide.

• Read the premises
• Assemble the Venn regions that represent them
• Identify the conclusion that genuinely follows
• Reject the conclusions that commit a fallacy

• Desktop: click region tiles and conclusion options; some choices are keyboard-accessible too
• Phone & tablet: tap tiles and answers, fully touch-driven

• Daily: the same arguments for everyone each day
• Practice: fresh arguments every run
• Easy, Medium and Hard add subtler fallacies and more terms

• Diagram what the premises force before looking at the conclusions
• Beware conclusions that overreach beyond what the regions guarantee
• Name the fallacy when you spot one, it confirms the rejection

Syllogica teaches formal logic and fallacy-spotting through hands-on region diagrams, making valid and invalid arguments visible.

• Skills: formal logic, syllogisms, logical fallacies, Venn diagrams
• Best for: roughly grades 8–12 (ages 13+)
• For parents & teachers: valid reasoning and common fallacies, made visual.

Syllogica is an original, free browser game that teaches formal logic and fallacy-spotting through hands-on region diagrams. It is built in-house and runs online.

A free, original browser game on PlayPendium. No download, no install.