On a recent ski-vacation, we bumped into one of my wife’s old school-friends. My wife was a little surprised, but not her friend. “Oh, I knew you were here,” she said. “I saw Alan’s posting on Instagram.”

Unwittingly, by sharing a photo on social media — just a nature scene, shot from a moving train — I had telegraphed to the world where my wife was, too. And she is not active on social media. So she was a bit shocked to discover that her location could be figured out so easily, based on my random nature photo (though fortunately she wasn’t upset about it). But this tiny incident underscored the profound changes that have occurred, in my lifetime, regarding how we share information about ourselves.

I’ve always been a sharer. I’m a writer, after all, and my books often combine a personal with an expository voice. If you read my first book, Believing Cassandra, you will learn a lot about the origins of the sustainability movement; but you will also learn a lot about me. I share personal letters and journal entries as a way of illustrating general points about data, history, or sustainability issues.

So for me, the transition to social media was a kind of seamless evolution. The phases look like this:

•    Phase 1. Letter writing: I wrote many long letters to friends and family, from my teen years.
•    Phase 2. Publishing in newsletters/magazines: I started publishing my writing around 1987.
•    Phase 3. Personal newsletter: In the early 1990s, following the example of my friend/mentor Donella Meadows, I started writing regular summaries of thoughts and activities and sending them, by post, to my circle of friends, contacts, and readers. Like her, I called them “Dear Folks” letters.
•    Phase 4. Listserves and e-newsletters: By the late 1990s I had shifted this activity over to email. This included sending around columns that were sometimes picked up and published.
•    Phase 5. Blogging: I started blogging seriously in 2008 (a bit late). Blog entries took the place of those earlier email newsletters and occasionally published columns. I more or less stopped submitting my work to other publications, though I continued to respond to invitations to publish (and still do).
•    Phase 6. Social Media: I started with Twitter and Facebook about the same time, but got more active later.

And here’s a pattern I notice: as time goes on, social media — the latest phase — is tending to obliterate the phases that went before it. Example: I blogged only eight times in 2014, compared to 20 times in 2012. I publish less than before. And I definitely write many fewer letters.

Why? Partly because people seem less and less interested.

I certainly don’t take this personally. There is a well-known enormous flood of information out there. What’s more, the majority of that flood is personal information: things like my nature photo, times a billion. In the old days, I was unusual (as are all writers) in that I shared personal information publicly. It was theoretically shared with the whole world, even if in practice the real numbers of people reading what I wrote were in the tens of thousands, tops.

Today, virtually everyone shares personal information publicly. Sometimes whether they want to or not (like my wife). And that information is far more accessible than my little newsletters ever were, whether they were on paper or in electronic format.

Skimming through Facebook or Twitter or Instagram, I am instantly in touch with hundreds of friends and contacts. All of them are sharing the kinds of thoughts that I went to great effort to push out into the world, back when I was writing my “Dear Folks” newsletters, printing up a couple of hundred copies, sticking them in envelopes and posting them.

Just more briefly.

Of course, social media is a great equalizer that way. We “writers” (and other kinds of artists) are not so special anymore. Anyone and everyone can now tell the whole world what they think, what they are doing, what they are planning to do, with a few clicks on that little handheld device we still insist on calling a “phone”.

What does this evolution mean for the future of personal communication? I have no idea. Perhaps the whole notion of actively informing people about what you think and do will die away. Robots will decide what we should publish on our social media timelines. Then robots will decide which of those pieces of information, published by others, we should read. (Actually, that’s what is already happening: Facebook’s automated algorithms determine whether what you publish there will actually appear on your friends’ timelines. How their robots make that determination is not public knowledge.)

But I note one more interesting pattern: the impact of this evolution, on me, is a reduced desire to share. Maybe it is also a function of getting older, but I feel less and less motivated to tell the world what I think — especially now that this act is now wrapped together with the culture of selfies, trolls, and hashtags. (That is, ubiquitous photographic narcissism, anonymous meanness to other people, and ever-shorter attention spans about what’s important in this world.)

Obviously, I do keep active on social media — hence this blog post, which I’ll also flag on Twitter and Facebook. Since I am still a writer (and songwriter), and want to at least give the world a chance to discover my books and songs, I make sure to post things into the great flood of tweets and timelines on a regular basis. Sometimes I’m happily and pleasantly surprised by the response, too.

But to be honest, posting on social media is just a lot less fun than those “Dear Folks” newsletters I used to write.

And I notice that the things I post are less and less personal. I may post just as much as I ever did, but I share less than I used to.

Maybe I’ll end up back where I started — writing letters to friends and family, on paper. There remains a deep satisfaction, a visceral as well as intellectual pleasure, in physically tracing out one’s thoughts in a line of ink. Then sending the letter away, as a physical object in the world, to be received, opened, and read by another human being, sitting at a kitchen table.

It feels more like true sharing. I’m old-fashioned that way.