Dear Diary:

Passing through Grand Central Station, I noticed a man shouting into the crowd at the base of the escalators. My brain registered wild hair, scraggly beard, old clothes, shouting at no one in particular, and I took a half-step in another direction to give him a wider berth.

Then I realized the apparently homeless man was actually shouting at a young Asian woman who could have been cast as the confused tourist in any summer movie. She had tried to pass through the turnstile but her MetroCard had failed.

The homeless man was waving her back, saying: “You put it in upside down! Just turn it the other way!” She tentatively returned to the turnstile and did as instructed, but this time she got the “swipe again” message.

“Don’t worry,” he explained, “just do it again, this time straight through. Don’t hesitate.” She followed his instructions and a huge grin lighted her face when she finally made it through.

The young woman stopped on the other side, said something I could not hear and bowed slightly. The homeless gentleman bowed in response, then turned and shuffled away, a reminder that grace and human kindness can come from unexpected sources.

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