FWIW, some college friends of mine conjectured that it was an evolutionary vestige of when early man would be sitting around a fire and occasionally stop and look around to see if he was being stalked by something higher on the food chain.
Hence, “predator check.”
I’m thinking Telemark and I might be of a similar generation (sorry, if that’s not so - since my generation remembers Mr. Wizard. In fact, I’m so old, when I was a kid, computers were made out of wood.) Anyway, when one of those pauses would happen, we used to say it must be 20 minutes past the hour, or 20 minutes to the hour. And, aside from the fact that the empirical evidence had little impact on us, because that didn’t often seem to be the case, we kept up with that little fiction, apparently believing that we were close enough, and pursued that line of babble through countless evenings together through high school and college.
It’s 4:20.
My Uncle once told me about reading a sci-fi story about this particular phenomenon, probably the same one you’re referring to. The gist was that our alien/superdimensional creators implanted an instinct in us to listen for their advice, and all we had to do was quiet down and listen at śpecific times. So now we all go quiet at twenty minutes past or twenty minutes to the hour, in oreder to listen to what they have to say.
I’ve never heard of such a thing before, which would give credibility to Snopes thesis that it’s an American concept entirely.
I can see how it makes sense that it gets quiet twenty after - after twenty minutes, you tend to run short of things to talk about, after having gone through all the classic topics (the career, the family, the weather, etc.). As some people in the room starts to lose interest in talking, the atmosphere will spread throughout the room and shortly everybody will have stopped talking.
That’s my take on it. I obviously don’t believe in Abe Lincoln, I never met him in person. 
A hostile audience. 
hushed - A hush fell on the room.
We’ve always called it “the seven minute lull” - a theory that every seven minutes, there’s a lull in conversation. Sometimes it doesn’t stop completely, just wanes for a second in volume or speed, and other times it’s a full stop. I actually did sit with a stopwatch and a notebook in a Starbucks once, and it seemed to have some creedance.
A friend of mine used to refer to that as “preacher walked by.” Indicating, of course, that since we all usually talk about things we don’t want the preacher to hear, we instinctively stop talking when we see him drawing near.
Harmonic Convergence
I always think of it as “an angel passing,” even though I don’t actually believe in angels. My grandmother and her family always said that, and it’s stuck with me.
has anybody considered the question of volume (loudness)?
In a large group, 2 individiduals talk much louder than normal conversation.
So in a room with a dozen conversations going on, it gets noisy. Then, if one conversation between 2 people stalls, the others next to them suddenly realize they are shouting unnecessarily, so they lower their voices. Then the next couple does the same, and it spreads rapidly. Suddenly, the noise level is much lower, and everybody at the party becomes very self-conscious that whatever they say next will be heard by all, so they quiet down,…fast.
result—simultaneous silence, and a bit of embarrassment for all.
You know, I really like this theory for why it happens. Have no idea how accurate it is, but it just kinda falls in with the sort of stuff I think is neat.
I’m an American, and a Lincoln fan, and I’ve never heard of this before. Weird.
When I was in college, we also would look at our watches to see if it was 20 of or 20 after when this happened–or within 20 minutes of either!
I’d also suppose it’s some sort of negative feedback, much the reverse of the positive feedback that is the reason why some restaurants are so unnervingly loud: Once there is a certain degree of loudness in a room, everybody will speak louder to make himself heard by his conversation partner, and this inceases overall volume again and makes people speak even louder.
The angel passing syndrome, as I’ll refer to it for sake of brevity, could also be the result of coincidentally syncronous pauses in several conversations (wow, what a sentence). Most talks will have a short pause of a few seconds once in a while when nobody says anything. It’s not too likely that a specific pause will coincide with similar pauses in other conversations, but on the long run, it’s very likely to happen sooner or later coincindtally - another application for probability theory. When a significant number of talks is involved, the overall volume in your room will suddenly decrease, and as nobody of the people will dare to break the silence, everybody hushes.
And the 20 minutes to/after the hour? Not too unlikely either. I’d guess a superstitious person who believes in the Abraham Lincoln myth would also consider a sudden silence occuring at 10:18 or 10:23 to fit this legend. Probably a 5 minutes derivation would be acceptable to them. This gives you a ten-minute time slot for 20 minutes after the hour and another one for 20 minutes to the hour - 20 minutes in total every hour. So one in three angel passing syndromes will fit, and selective memory makes us remembering this one and not the other two that occured “at the wrong time.”
I had heard the “20 after” rule somewhere along the line, but any time it happened at 20 after, I’d say “Huh, it’s 20 after” and I’d suddenly realize that no one ever knew what I was talking about. Glad to know that I am not the only person to have heard of it.