A doctor once boasted of his expertise in surgical treatments.
One day, a general was struck by an enemy arrow on the battlefield. The arrow had penetrated his flesh, so he summoned the "surgeon".
The general explained his predicament. The "surgeon" repeatedly assured him, "This is easy to treat! Very easy!"
He picked up a pair of sharp scissors and, with a snap, cut off the exposed shaft of the arrow. Handing the shaft to the general, he declared, "Done. Now, please pay me."
The general was left speechless, not knowing whether to laugh or cry. "The arrowhead is still inside my flesh," he protested. "You must remove it quickly!"
To this, the "surgeon" replied, "The arrowhead lodged in the flesh is a matter for internal medicine. That has nothing to do with my 'surgery'."