A fat man leading a group of people out of a cave on a coast is stuck in the mouth of that cave. In a short time high tide will be upon them, and unless he is unstuck, they will all be drowned except the fat man, whose head is out of the cave. [But, fortunately, or unfortunately, someone has with him a stick of dynamite.] There seems no way to get the fat man loose without using [that] dynamite which will inevitably kill him; but if they do not use it everyone will drown.
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What should they do?