Shortly after I moved to New York City in 1998, a friend introduced me to the head of a local options market-making firm. A few days later, I was asked to join his team on the American Stock Exchange as a trader. Was it because of my background in finance? No, I had none. I didn’t even know the difference between a call and a put. Why did they make the offer? Because I was a top-flight bridge player, and bridge and trading had a well-known link that had been exploited before by firm heads on the floor.