Are you really sure that a floor can't also be a ceiling?

M. C. Escher

About M. C. Escher

Portrait of M. C. Escher

Maurits Cornelis Escher (Dutch pronunciation: [ˈmʌurɪt͡s kɔrˈneːlɪs ˈɛʃər]; 17 June 1898 – 27 March 1972) was a Dutch graphic artist who made mathematically-inspired woodcuts, lithographs, and mezzotints.

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