What distinguishes man from animal is language, but this is not a natural given already inherent in teh psychophysical structure of man; it is, rather, a historical production which, as such, can be properly assigned neither to man nor to animal. If this element is taken away, the difference between man and animal vanishes, unless we imagine a nonspeaking man – Homo alalus, precisely – who would function as a bridge that passes from the animal to the human. But all evidence suggests that this is only a shadow cast by language, a presupposition of speaking man, by which we always obtain only an animalization of man (an animal-man, like Haeckel's ape-man) or a humanization of the animal (a man-ape). The animal-man and the man-animal are the two sides of a single fracture, which cannot be mended from either side.
from The Open: Man and Animal, page 36
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