"a group of hunters have tracked a large stag, and found it to follow a certain path. If all the hunters work together, they can kill the stag and all eat. If they are discovered, or do not cooperate, the stag will flee, and all will go hungry.

The hunters hide and wait along a path. An hour goes by, with no sign of the stag. Hours pass, with no trace. The stag may not pass every day, but the hunters are reasonably certain that it will come. However, a hare is seen by all hunters moving along the path.

If a hunter leaps out and kills the hare, he will eat. However, it results in the trap laid for the stag to be wasted, and the others will starve. There is no certainty that the stag will arrive; the hare is present. The dilemma is that if one hunter waits, he risks one of his fellows killing the hare for himself, sacrificing everyone else. This makes the risk twofold; risk the stag never coming, or risk another man taking the kill.
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