A battleship is travelling through some very thick fog, when directly in
front of them lights are seen. The Captain gets on the radio to the other
party.

Captain: You must change direction by 20 degrees immediately.

Reply: No, you must change direction

Captain: I am a Captain, you must change direction by 20 degrees
immeadiately.

Reply: Well i'm a leading seaman, YOU must change direction

Captain: (Enraged) Well i'm a battleship, YOU MUST change direction
immeadiately by 20 degrees.

Reply: Well I'm a lighthouse.....