The drained expanse of McCarren Park Pool, August 9, 2007. That’s the last time I saw Beastie Boy MCA alive. Not like I knew him; not like I wasn’t sharing the experience with 5,000 other people.

And yesterday, on Facebook, on Twitter, on Youtube, a whole slice of usually too-preoccupied-with-its-own-mortality-to-participate-in-civil-society Gen X rumbled to life to mourn his passing.

All the best tributes were public and immediate.

(The Times has a bunch more of these.)

Twitter filled up with #RIPMCA, as did the comments on every Beastie Boys video on YouTube. Those of a certain generation couldn’t open Facebook without seeing another Adam Yauch meme.

It’s moments like these when it feels as if grieving is exactly what social media is for. Like it’s better at this than pretty much anything else, including celebration (too remote, and liable to inspire jealousy), the everyday (too trivial) or anger (too much like bitterness or schadenfreude).

Whether or not you care who MCA was, the expressions on social media feel authentic, maybe because they’re unadorned, straightforward and nakedly imperfect. Everyone who writes about their grief knows in advance that words fail, so the usual look-at-me temptation to be too clever by half disappears.

Sherry Turkle, professor at M.I.T. and author of “Alone Together: Why We Expect More From Technology and Less From Each Other,” recently described in the Times how we use mobile devices and social media to filter and sanitize our interaction with the real world.

We are tempted to think that our little “sips” of online connection add up to a big gulp of real conversation. But they don’t. E-mail, Twitter, Facebook, all of these have their places — in politics, commerce, romance and friendship. But no matter how valuable, they do not substitute for conversation.

So do a thousand microblogged tributes to MCA mean anything to all the Gen Xers who thought they would be young forever, but who discover that, to a degree that makes the realization as mundane as dust, they too will die? What conversations aren’t happening because we’ve dispensed with our grief in the “safe” realm of the Internet?

But that, I think, is too cynical a view. Expressions of grief have always been public – that’s the catharsis part of the process. That’s what social media is good for.

In the case of grief, at least, Turkle’s thesis doesn’t quite apply. Because in any age, after all the public mourning is done, the unchangeable core of the human condition is that we are all very much alone, privately meditating on death and its implications for ourselves.

Seen in this light, the title of Turkle’s book, “Alone together,” becomes the ultimate testament to the therapeutic power of social media. We don’t need technology or a dissertation on its impacts to tell us that we are alone. But surely it’s all the better to be alone, together.