A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.
Douglas AdamsThe kakapo is an extremely fat bird. A good-sized adult will weigh about six or seven pounds, and its wings are just about good for waggling a bit if it thinks it's about to trip over something - but flying is out of the question. Sadly, however, it seems that not only has the kakapo forgotten how to fly, but it has forgotten that it has forgotten how to fly. Apparently a seriously worried kakapo will sometimes run up a tree and jump out of it, whereupon it flies like a brick and lands in a graceless heap on the ground.
Douglas AdamsWe talked about how easy it was to make the mistake of anthropomorphizing animals, and projecting our own feelings and perceptions on to them, where they were inappropriate and didn't fit. We simply had no idea what it was like being an extremely large lizard, and neither for that matter did the lizard, because it was not self-conscious about being an extremely large lizard, it just got on with the business of being one. To react with revulsion to its behavior was to make the mistake of applying criteria that are only appropriate to the business of being human.
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