History of the Muddy Children Puzzle

Hans van Ditmarsch

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arXiv · 2606.13703

History of the Muddy Children Puzzle

Hans van Ditmarsch

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Abstract

The Muddy Children Puzzle is a puzzle about knowledge and ignorance that has been inspiring for the development of epistemic logic. Who came up with it first? This is unclear. We trace the origin of the Muddy Children Puzzle through logical and literary publications over the past two centuries. The puzzle inspired a numerous variations such as involving numbers or coloured hats. We also present a novel hats puzzle involving self-reference.

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Hans van Ditmarsch. 2026-06-08. History of the Muddy Children Puzzle. https://arxiv.org/abs/2606.13703

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