A western businessman was conducting his Japanese guest around the busy city. Because of traffic congestion they used bus and underground railway. The businessman was proud of his local knowledge of the system, and by clever use of the map and timetable, he got them to their various destinations much quicker than the average tourist could have done. He was particularly proud of one trick: "There, we saved twenty minutes by changing trains and taking the other line".

The Japanese smiled broadly. When they got to their station, the businessman hustled the other up the stairs, and out into the fresh air.

Nearby was a secluded little grassy area with some seats. The Japanese sat down, and looked benevolently on the world passing by.

"Hey, what are you doing just sitting there?" gasped the western businessman.

"Oh, I'm just using up the 20 minutes we saved on the train".