A doctor, a lawyer and a real estate agent were discussing the relative merits of having a wife or a mistress.
The lawyer says: "For sure a mistress is better. If you have a wife and want a divorce, it causes all sorts of legal problems."
The doctor says: "It's better to have a wife because the sense of security lowers your stress and is good for your health."
The real estate agent says: "You're both wrong. It's best to have both so that when the wife thinks you're with the mistress and the mistress thinks you're with your wife -- you can go and sell some homes.