They had been struggling on in the line all day, puzzling their way around a series of obstacles in search of a door. Many had fallen, and the morale of the group was low.

"So what's it all about then?" asked one young lemming. His feet were sore from the interminable walking, and he had lost some close friends that day.

"Eh?" asked an older lemming marching just behind him.

"You know, all this plodding along, building stuff and blowing ourselves up. Why do we do it?"

"Ah, that's easy." said the old lemming with a patient smile. "Because it is there."