Izzy rings the bell of a very wealthy person's house in New York and when the owner comes to the door, Izzy greets him.
"Sholom Aleichem, Mr. Goldstein,” says Izzy. “I'm collecting for the local Jewish school, and I'm wondering if a nice wealthy Jewish person like yourself wouldn't want to make a little contribution."
"The name is Gold, not Goldstein,” says the man, “And I am not Jewish."
"Are you sure?" asks Izzy.
"But it says here that you're Jewish and my records are never wrong."
"I can assure you that I am certainly not Jewish", replies Mr. Gold impatiently.
"Look sir, you wouldn’t be lying to me would you? My records are never wrong – you must be Jewish!" demands Izzy.
"For the last time, I am not Jewish, my father is not Jewish, and my grandfather, alav hashalom, wasn't Jewish either!"