It is broadly logically impossible that there be a hand that both draws itself and is drawn by itself. So what the Escher print represents is B-L impossible, and in this sense 'incoherent' and 'unintelligible.' But the Escher drawing itself is coherent and intelligible as a representation. And so we can say that we understand the drawing while also saying that we do not understand that which is depicted in the drawing.
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