Eugene Byrne is a freelance journalist and author, and a regular contributor to BBC History Magazine. You can read his online blog at http://eugenebyrne.wordpress.com/
In the early 1930s, a young man from a small town in upstate New York was visiting New York City.
While he was there, he decided to look up his older brother, who had moved to the city a few years previously.
His brother suggested they meet up at a fancy restaurant. "Don't worry," he said. "I'm paying."
They met, had dinner, talked about old times and the family, and how everyone was doing.
"And I can see you're doing well," said the younger man. "Eating in this swanky restaurant, tailored suit, silk tie ... So what do you do for a living?"
The man leans forward and says quietly. "To tell you the truth, I work on Wall Street. I'm in banking."
"I see," said the younger man.
"Now you have to promise me you won't tell our mother. She'd be really upset. She thinks I'm a piano player in a brothel."
That's a very old and well-worn one, and it certainly dates back to Depression era America, maybe even as far as the great Wall Street Crash of 1929.
Ever since then it's taken on a life of its own as a one-liner, and applied to various different professions ("Don't tell my Mom I'm a Congressman/lawyer/political lobbyist (etc.) - she thinks I play piano in a bordello.") but it was originally about bankers.
If you want to be pedantic about the time and place, you can see the gag actually has quite a lot of interesting things going on. Obviously it implies that working in a brothel is more respectable than banking, though if you happened to be tickling the ivories in one of the more upmarket places, and you had the talent, you could make very good money. Early jazz greats Tony Jackson and Jelly Roll Morton both forged careers in the "sporting houses" of New Orleans. Morton was living with his great-grandmother at the time - she threw him out of the house when she discovered that he'd been less than truthful when he told her he worked as a night-watchman.
During the Great Depression, just as now, many Americans blamed the banking industry for the nation's economic woes. Indeed, with hundreds of thousands of people standing in line at soup kitchens, feelings about banking ran far deeper than nowadays. One of the most startling things about President Franklin D. Roosevelt's inauguration speech, made at the depth of the Depression in January 1933, is the way he talked about bankers in a way which no mainstream politician would do nowadays. With quasi-religious language, he savaged what he called "the money changers": "Stripped of the lure of profit by which to induce our people to follow their false leadership, they have resorted to exhortations, pleading tearfully for restored confidence. They know only the rules of a generation of self-seekers."
(Read it in full here: http://historymatters.gmu.edu/d/5057/ *)
There are other Depression jokes, too, which get wheeled out with each financial crash, such as the one about the visitor to New York who's admiring all the expensive yachts in the marina. A local tells him they all belong to brokers and bankers. "And where are their customers' yachts?" asks the visitor.
Of course plenty of financiers lost their shirts in the Wall Street Crash of '29; the businessman told his secretary to get his broker on the phone. "Certainly sir," she said. "Stock or pawn?"
Though obviously successive crashes bring their own jokes as well. As in 1987: What's the difference between a seagull and a yuppy? A. The seagull can still make a deposit on a BMW.
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