Read: The geography of Hong Kong’s protests

Along with those meetings, I have written essays about Joshua’s actions and the way the local authorities have tried to silence him. I’ve seen three documentaries dealing with him, and in one of these, Joshua: Teenager vs. Superpower, I appear as a commentator.

How could I not remember Joshua?

“You remember me!”

I wondered at first whether he was intentionally being silly when he smiled and said those three words, but I quickly dismissed that possibility. Just before he noticed me walking toward him, he looked burned out and downcast. And there had been no frivolous moments during our two previous encounters. Serious, smart, dedicated, determined: These were adjectives I associated with him, but not silly.

Even if trying to amuse me was the furthest thing from his mind when he spoke, I chuckled over his words right after he said them. I laughed again several times during the rest of my week in Hong Kong as I told friends about our meeting, turning it into a comic anecdote. A few days after leaving the city and returning to California, though, I stopped finding his comment funny. Instead, I started to feel a sense of heartbreak.

It doesn’t take much to make me laugh, but I don’t cry easily. So it was a bit of a shock when, thinking back to seeing him while I rode my bike to the gym one morning, I felt tears welling up in my eyes.

At the time, I couldn’t figure out why I felt like crying. I now know that I was not just shedding tears for a young man I barely know. I was also mourning the demise of a special place. I was lamenting the slow death of Hong Kong, or rather of a particular Hong Kong.

Read: The blurring boundaries between Hong Kong and mainland China

A Hong Kong that was supposed to be able to enjoy a variety of distinctive freedoms relating to speech and assembly for 50 years after becoming integrated into the People’s Republic of China under the terms of a “one country, two systems” arrangement. A Hong Kong that has been altered by seemingly unstoppable processes that have transformed the difference between its way of life and that of urban centers across the border from a chasm to a gap.

That Hong Kong is not just in its death throes, but is imagined by some to have already died. This could explain why Joshua’s face lit up when I approached him. There is good cause for activists like him, famous or not, to be heartened by any sign that people who do not live in Hong Kong continue to care. That efforts to stem, at least partially and at least for a time, the city’s becoming more like an ordinary part of the mainland have not gone unnoticed.

“You remember me!”

Those words don’t haunt me as regularly as they did on the first day I cried thinking about Joshua saying them, but I still think back from time to time to that evening when he said them and find the memory heartbreaking.