When I entered the nearly empty bar near Grand Central, I was unsurprised—and, I’ll admit, rather pleased—to see, sitting on the stool he’d occupied when I was in the bar some months before, the mature gentleman who had told me that the economic crisis was inevitable once smart people started taking jobs on Wall Street. (“Our guys would have never invented credit default swaps,” he’d explained. “They couldn’t have done the math.”)

I settled myself a few stools away, but I did nod; in return, he lifted his martini in my direction as a sort of understated toast. He was dressed, as he’d been the other time I saw him, in gray trousers and a tweed jacket and a blue button-down shirt—none of which differed from what could have been purchased in close proximity to a New England college campus in 1959. Again, he was wearing a club tie. This time, it appeared, from my vantage point, to be decorated with tiny artificial-heart valves.

No sooner had I ordered a drink than we had occasion to exchange glances that communicated dismay: Three men who were sitting at the other end of the room had begun discussing wine in voices that seemed intended to enlighten oenophiles who were strolling past Rockefeller Center.

The man at the end of the bar nodded in their direction and said, “Among people who think of themselves as wine connoisseurs there’s a 61 percent ACI.”

I was puzzled. “What’s an ACI?” I asked.

He lowered his voice a bit, as if he was about to use somewhat offensive language and wanted to make certain no women (he would have said “ladies”) were in ear-shot. “Asshole Correlation Index,” he said.

I said, “You mean that 61 percent of people who talk a lot about wine are—”

“Correct,” he said, before I could finish. “That’s not even particularly high, as these things go. That means that nearly 40 percent of people who think of themselves as wine connoisseurs are people who have learned a lot about wine for one legitimate reason or another and are not pretentious about it. Those guys over there are in the other 61 percent, I’d wager. When they get through analyzing a few pinot noirs that they wouldn’t actually be able to tell apart, they’ll probably turn to cigars or single malt scotch. People who spend a lot of time discussing both cigars and single malt scotch, by the way, have a 78 percent ACI. That’s high—much higher than connoisseurs of either one singly. If you add wine to those two, it’s off the charts.”

“But how do you arrive at these ratings?” I asked.

“I have my methods,” he said. “You’ve seen those World War II movies where the German line officer is talking to the downed American pilot in a room where a blond guy in a long leather coat is sitting silently, and the officer is saying, ‘I hope you’ll agree to tell us what we want to know. If not, Herr Mueller here has his methods.’ Well, think of me as Herr Mueller.”

“But aren’t you stereotyping people?” I asked.

“Only a certain percentage of them,” he said. “For instance, what do you think when you see a guy who’s wearing a blazer over a sport shirt, and the shirt is unbuttoned nearly to the navel? What’s your first reaction?”

“Creep,” I said.

“Not me,” he said. “I think 93 percent ACI. Admittedly, that’s high. It’s one of the highest ACI’s on record. It’s 25 points higher than the ACI for males who wear designer jeans and 12 points higher than males who wore Nehru jackets or bell-bottom pants in the ’70s. But it still leaves room for the 7 percent who have their shirts unbuttoned for some reason that makes perfect sense—maybe a skin condition that requires them to keep air circulating across the chest hairs at all times. So you might say that the ACI is a device that allows some people to be a bit more tolerant than some other people—no offense.”

That sounded disturbingly logical. Also, although I wasn’t quite ready to say so out loud, I’d been thinking that a 93 ACI for the guys with unbuttoned shirt was a bit low. Also, I happen to have in my safety-deposit box a list of people I know who wore Nehru jackets in the ’70s.

“Or take the example of East Hampton, a community known for its luxurious summer homes,” he went on. “I believe you were once overheard to say that anybody who could take a bicycle ride around East Hampton and not be turned into a Marxist by the hedges—just the hedges—can be considered safe for capitalism.”

“How did you know what I said about the hedges?” I asked.

“I try to keep up,” he said, as if it were perfectly normal to keep up with the conversation of someone he’d seen only once before. “At any rate, the ACI for people who live behind particularly imposing hedges is 61—coincidentally, the same as the ACI for people who talk a lot about wine. Of course, people who live behind the hedges and also talk a lot about wine have an ACI of 82. I haven’t calculated yet how much that goes up if they also take their winter vacations in St. Bart’s during the party season there, but there’s definitely an increase. These things mount up.”

At that moment, we both realized that we had finished our drinks. “I’ll get this round,” the man said.

“No, I’ll get it,” I said. “I insist.”

“People who insist on getting the check have a 57 percent ACI, because a number of them are show-offs,” he said.

I threw up my arms in surrender. He signaled the bartender to bring us each another drink, and said, “That’s 9 percent higher than the people who always seem to let someone else get the check.”

“The next round’s mine,” I said.