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https://doi.org/10.1093/mind/fzae061
Image: Mind

For his article “A Universal Money Pump for the Myopic, Naive, and Minimally Sophisticated Open Access,” in the April 2025 issue of Mind, philosopher Johan Gustafsson devised this minimal paradoxical stairway to illustrate a cyclic ranking: A appears higher than B, B appears higher than C, and C appears higher than A.

Two other perplexities, while we’re at it — by Mike Tolleb:

https://commons.wikimedia.org/wiki/File:Faux_Escalier.JPG
Image: Wikimedia Commons

And by Wikimedia user Mabit1:

https://commons.wikimedia.org/wiki/File:Unmoegliches_Objekt_4.svg
Image: Wikimedia Commons

(Thanks, Johan.)