analogies

This one made J. happy:

Driving along Memorial Drive on the way home from Trader Joe's the other night, Sam was asking us to name all the bridges we passed. One of them was the Weeks Footbridge, and J. asked Sam if he knew why it was called a footbridge. Sam thought for a minute then figured out, because it's for people to walk on, not for cars. Then he thought for another minute and noted that the other bridges should be called wheel bridges. He has a point, there.