Wearing a GoPro camera hidden in his hat (Ohio has one-party consent), McCormick captures his exchanges. The reactions in this video vary: A Vietnamese employee breaks into instant laughter and a smile; two young men from Honduras are stoic but deeply curious about his methodology; a woman from Kenya is proud of him, and insists he keep practicing.

McCormick also learns as he goes. Two men tell him his way of saying “I’m married” in Somali could sound more to a native speaker like “I am a wife.”

Not all the people he approaches are immediately open to talking. “I’m a 6’6” black guy, I’m approaching you, I’ve gotten—people look a little scared, I guess nervous,” he says. “They don’t understand what this guy is doing. But once this language turns on, it’s like a totally different person.”

McCormick says he’s fluent in Chinese and Japanese, which by his definition means that he can express whatever he wants in the language, and can explain around any limitations in vocabulary. (That probably doesn’t track with a linguist or college language teacher’s definition, and indeed McCormick has critics online who take issue with his lack of formal training.)

By my own assessment, McCormick’s aisle-wandering pays off: His Vietnamese vocabulary is pretty limited, but his pronunciation is quite good for an American. He’s largely self-taught, working from books by companies like Assimil and practicing with people he meets online and in person in Columbus. McCormick says his goal isn’t to go deep on just a few languages so he can discuss the news or read literature, nor does he focus at first on grammar—he’s far more interested in sounding natural while holding basic daily conversation.

As a result, McCormick’s methodology, while it yields some pretty good advertising for his business, serves primarily to surprise and delight strangers. And that, too, is a main motivation for him.

“It’s like a drug, like dopamine, for me,” says McCormick. “When I walk up to someone and speak to them…They get really excited—that’s just a couple phrases—but something about that first encounter, that’s really addictive.”

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