Square circles (the taxicab geometry)

pp. 217-219

in: Karl Menger, Selected papers in logic and foundations, didactics, economics, Berlin, Springer, 1979

Abstract

Square circles or round squares have haunted many and diverse philosophical writers as the archetype of the impossible and the absurd; they were assigned a place near — or rather below — golden mountains, unicorns and mermaids. They have been discussed by Thomists, existentialists and linguistic philosophers as well as by Herbart, Bergson, Russell and many, many others.