long ago, in a battle a soldier was shot in the leg, and suffered from constant
pain. An officer in the troop sent for a surgeon versed in external medicine to
treat the soldier's wound.
The surgeon came to have a look, then said, "This is easy!" He cut off
the arrow shaft at the leg with a big pair of scissors, and immediately asked
for fees for the surgical operation.
"Anyone can do that," the soldier, getting upset, cried, "The
arrow head is still in the leg, why haven't you taken it out?"
"My surgical operation is finished. The arrowhead in your leg should be
cured by a physician who practices internal medicine."