That humans were but one of a great chain of beings, stretching from the lowliest animalcule to the glorious invisible order of the angels, was an idea extended from Aristotle, not foreign even to the philosopher Locke. The material kernel of this notion became the content of Darwin's assault upon the confines of the Victorian mind. Nowadays the kinship of human and animal nature is commonplace, marked daily in medical practice by the purposeful sacrifice of mouse and monkey in the laboratory and the vaccine plant. It is less evident that the vital distinctions between the animal world and homo sapiens (or anyway homo faber—for I write as the 101st Airborne flies to Little Rock) can be discerned in laboratory experiment. But recently some of the deepest-lying studies of the psychiatrist have been set in an illuminating light by studies made upon garden spiders; the whole account seems to come very close to the beginnings of an answer to the ancient philosophical question: what is human nature?
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