SOMETIMES, I FEEL as though I am the missing link.

I walk upright, more or less, like a modern man. But my primitive tools place me in the Stone Age.

I do not, for example, wield an iPhone. I use but a simple (forgive the obscure reference) cell phone. Nor do I own a Blueberry (Strawberry? Raspberry? Whateverberry). Rather, I communicate in the way of the ancients, by desktop computer.

Now and again, I try to evolve.

Not long ago, I caught a glint of something I didn’t recognize. It appeared like a sparkly stone amid someone else’s rock pile.

I approached, scrunched up my face, and pawed it with curiosity. Hmmm, I thought, This must be the new thing everyone is talking about.

Then the tiny brain behind my sloping forehead had an idea. The idea was at once simple and confounding. I could not figure out why I would do what it seemed my brain was instructing me to do. Maybe it was to see what all the hubbub was about. Maybe it was to try to plant my feet and club, once and for all, into the clay of the twenty-first century.

Whatever the reason, I did it: I opened an account on Facebook.

DING.

My prehistoric e-mail world just received something from the au courant Facebook world. Apparently, the modern reaches out to the ancient just as a strong mountain climber offers his hand to a struggling climber.

From: Wallmaster+pr=zz=fz@facebook.com

Subject: Someone More Advanced Than You [not her real name] wrote on your wall.

Why, I wonder in my prehominid way, are they telling me this? What is my wall? And who is this Wallmaster?

I go to Facebook and type in my name and password. Up comes my page, if that is what it is called. On it, over on the lower right, I see a message from More Advanced.

Is that my wall? Why do they call it a wall? Maybe I will ask the Wallmaster.

I think about responding, but my big, bushy eyebrows are furrowing with confusion. Can everybody read what is here? If so, can everybody also read my reply?

I slink away from the wall. I go back to the safety of my cave, which is to say, my e-mail.

In my e-mail reply to More Advanced, I say that I feel like George trying to keep up with the treadmill on the old TV cartoon The Jetsons: “Jaaane! Stop this crazy thing.”

In the subject line of my e-mail reply, I write “Off the Wall.”

I feel like that in more ways than one.

DING.

From: confirm+pr=zz=fz@facebook.com

Subject: Some Other Guy [not his real name] added you as a friend on Facebook.

Oh nooo. Not that guy! I didn’t like him when I knew him, briefly, two decades ago. Actually, I never knew him. We never hung out, never stepped inside each other’s house, never even called each other. Now, all of a sudden, he’s a friend?

Ding.

From: confirm+pr=zz=fz@facebook.com

Subject: Linda Whowhat [not her real name] added you as a friend on Facebook.

Who is this person? Is she someone with whom I shared a laugh, a drink, a night of Twister?

Whereas previous ages were marked by the discovery of fire or the invention of the wheel, the milestone for the current age is our constant availability and instant intimacy.

The past, present, and future fuse into one ever-expanding universe of friends.

Six degrees of separation? Forget it. Now, there are zero degrees of separation.

It is as if we are all living in our own, and each other’s, personal memoir -- except this memoir unfolds in real time and is not edited to keep out the boring parts. And there are a lot of boring parts.

Lisa Banalitino [not her real name] is clipping her toenails.

Sidney Nothingtodo [not his real name] is about to mow the lawn.

Pat Sleepinstein [not his real name] is changing the sheets.

BEING ON FACEBOOK is a little like inviting all the marauding hordes into your home. It is to walk down the driveway and unlock the gate for the barbarians.

Yet I play along. Or try to. Facebook asks me to disclose my marital status. I do: married. It also asks me to include my spouse’s name. I do: Jessica [her real name].

Except I don’t. It seems that, because Jessica doesn’t have a Facebook account, her name will not appear in the little box.

Kind of antisocial for a social network, don’t you think?

Maybe I’ll take it up with the Wallmaster. But first, I have to master this fire thing.