Courtesy of Geoff:

two men and a woman are shipwrecked on a deserted island. for weeks they tried to devise ways off the island but to no avail. after a few months, human desire took over, and the three succumbed to what was natural...one day, the woman suddenly had an attack of conscience. she thought to herself, "this is wrong, i can't be sleeping with two men at once, it's immoral, i'm a horrible person..." unable to lift herself up from the pit of shame and depression, she took a plunge off a cliff and killed herself. the men were horrified, but they went on with life, and gradually, they again succumbed to what was natural...one day, one of the men said to the other, "this is wrong, this is just not right." "i agree," said the other, "we should bury her."