The Mathematicians (Joke)

[postman]

Three mathematicians were walking down to the railway station one day,
deep in conversation about mathematics. They were so absorbed in what
they were talking about that as they approached the station, they failed to
hear the announcement that the train was about to leave.

However they did notice when the train started to pull away from the
platform. Alarmed, they started to run after the train, and eventually two
of them managed to scramble on board.

A station porter noticed the remaining man looking glum. "Never mind",
he said, "Two out of three isn't bad."

"But you don't understand," replied the mathematician, "they only came
to see me off."