开个玩笑，不过在他的 Hen with Egg, 明显是一个 公鸡：）
像公鸡其实也说明回答这问题关键，必须有外力作用才行。
上网查，他著名的 Drawing Hands, 才真正的说明了这个问题。
抄一段: M.C. Escher: Impossible Possibilities
One of Escher’s most indelible images is the lithograph Drawing Hands. Here we have a restatement of the chicken-and-egg paradox, with each hand drawing the other into existence, going from mere outline into fully-shaded illusionistic three-dimensionality. Whether one thinks of it as a meditation on creativity or as a sort of optical Zen koan, once seen, this work is hard to forget. In works based on reflections, Escher found distortions of space ready-made, in the way polished curved or spherical surfaces render an image. Hand with Reflecting Sphere is an eloquent self-portrait in which the artist’s hand is the only part of his body that is directly seen; his face and torso, as well as the room he occupies, are all magically encompassed, by way of reflection, in the metallic globe the hand is holding.
