"Economics is the only field in which two people can get a Nobel Prize for saying the opposite thing" is true, but is not strong enough. Better:
"Economics is the only field in which two people can share a Nobel Prize for saying opposing things." Specifically, Myrdal and Hayek shared one.
(Quoted off a webiste)
Next is a bit over the line in my book:
A mathematician, an accountant and an economist apply for the same job.
The interviewer calls in the mathematician and asks "What do two plus two equal?" The mathematician replies "Four." The interviewer asks "Four, exactly?" The mathematician looks at the interviewer incredulously and says "Yes, four, exactly."
Then the interviewer calls in the accountant and asks the same question "What do two plus two equal?" The accountant says "On average, four - give or take ten percent, but on average, four."
Then the interviewer calls in the economist and poses the same question "What do two plus two equal?" The economist gets up, locks the door, closes the shade, sits down next to the interviewer and says "What do you want it to equal?"
One of my favorites:
An economist is a trained professional paid to guess wrong about the economy. An econometrician is a trained professional paid to use computers to guess wrong about the economy.
And last but not least:
"Economists do it with models"
Also;
"Economists do it with Slutsky matrices."
EDIT: here is more:
"An Indian-born economist once explained his personal theory of reincarnation to his graduate economics class. "If you are a good economist, a virtuous economist," he said, "you are reborn as a physicist. But if you are an evil, wicked economist, you are reborn as a sociologist."
"Economics is the only field in which two people can share a Nobel Prize for saying opposing things." Specifically, Myrdal and Hayek shared one.
(Quoted off a webiste)
Next is a bit over the line in my book:
A mathematician, an accountant and an economist apply for the same job.
The interviewer calls in the mathematician and asks "What do two plus two equal?" The mathematician replies "Four." The interviewer asks "Four, exactly?" The mathematician looks at the interviewer incredulously and says "Yes, four, exactly."
Then the interviewer calls in the accountant and asks the same question "What do two plus two equal?" The accountant says "On average, four - give or take ten percent, but on average, four."
Then the interviewer calls in the economist and poses the same question "What do two plus two equal?" The economist gets up, locks the door, closes the shade, sits down next to the interviewer and says "What do you want it to equal?"
One of my favorites:
An economist is a trained professional paid to guess wrong about the economy. An econometrician is a trained professional paid to use computers to guess wrong about the economy.
And last but not least:
"Economists do it with models"

Also;
"Economists do it with Slutsky matrices."
EDIT: here is more:
"An Indian-born economist once explained his personal theory of reincarnation to his graduate economics class. "If you are a good economist, a virtuous economist," he said, "you are reborn as a physicist. But if you are an evil, wicked economist, you are reborn as a sociologist."