One sealed envelope contains twice the money in the other; this puzzle exposes faulty reasoning that seems to favour switching whichever one you chose.

Think it. Then flip it. ahamoraTap to reveal Back to the cue

Math & LogicOne small aha

Your new ahaThe Two Envelopes Problem

The Two Envelopes Problem: Seems to always favor switching envelopes regardless of contents. Source: Two envelopes problem ↗

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12In this two-player game-theory scenario, individually rational betrayal can leave both worse off than cooperation.RECALL
The Prisoner's Dilemma
The prisoner's dilemma shows individually rational choices can leave both players worse off, a founding game theory scenario.
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13This ancient Greek philosopher's paradox divides a journey into endlessly smaller distances to challenge the possibility of motion.RECALL
Zeno's Paradox
Zeno's paradox argues motion is logically impossible by endlessly halving the distance left to travel.
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14This identity puzzle asks whether a vessel remains the same object after every plank is replaced.RECALL
The Ship of Theseus
The Ship of Theseus questions whether an object remains itself once every part has been replaced.
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