One Saturday, an Irishman walks into a pub in New York, orders three pints of Guinness, and takes a seat at a booth in the back. He sips from one beer, then another, and another, until all three are gone. The barkeep watches but says nothing.
The next Saturday, the same Irishman comes into the bar, orders three pints, and starts sipping away at the beers. This time, the barkeep feels compelled to say something.
"You know, the beers would taste better if you ordered and drank them one at a time."
The Irishman looks at the barkeep, then back at the beers, and starts to explain:
"It looks odd, but it's a family tradition. See, I live here in New York, my brother lives in Sydney, and my other brother lives in London. Every Saturday, we each go to a pub and have a beer for each other. It helps us keep in touch."
Satisfied with the explanation, the barkeep goes back to the bar. And each Saturday, for weeks and months on end, the Irishman heads to the pub, where there are three pints waiting for him.
One Saturday about six months later, the Irishman comes into the pub, but instead of taking the three pints, he explains that he'll only be needing two pints that day.
"Sorry to hear about your brother," the barkeep says.
"Huh? Oh, my brother," the Irishman explains. "No, they're both fine. See, I've just quit drinking."