Collusion Course
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Through the pitch-black night, the captain sees a light dead ahead on a collision course with his ship.
He sends a signal: “Change your course 10 degree east.”
The light signals back: “Change yours, 10 degrees west.”
Angry, the captain sends: “I'm a navy captain! Change your course, sir!”
“I'm a seaman, second class,” comes the reply
“Change your course, sir.”
Now the captain is furious
“I'm a battleship! I'm not changing course!”
There is one last reply
“I'm a lighthouse
Your call.”