You move!

[Akasha]

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.�