A doctor and a lawyer were attending a cocktail party when the doctor was approached by a man who asked advice on how to handle his ulcer.

The doctor mumbled some medical advice, then turned to the lawyer and asked, "How do you handle the situation when you are asked for advice during a social function?"
"Just send a bill for such advice" replied the lawyer.

On the next morning the doctor arrived at his surgery and issued the ulcer-stricken man a $50 bill. That afternoon he received a $100 bill from the lawyer.