Four surgeons were taking a coffee break and discussing their work.

The first one said, "I think accountants are the easiest to operate on. Everything inside them is numbered."

"I think librarians are the easiest," said the second. "When you open them up, all their organs are arranged alphabetically."

The third surgeon said, "I prefer to operate on electricians. Their organs are color-coded."

"You're all wrong," said, the fourth. "Lawyers are easiest. They're heartless, spineless(没有脊椎的）, gutless（没有肠子的） and their heads and asses are interchangeable."