I was recently talking to an intelligent 24-year-old Cambridge graduate. The conversation turned to TV comedy, and I mentioned Vic Reeves. The graduate had never heard of him. Nor had she heard of Bob Mortimer. This would have surprised me, but it’s happening a lot. Not Vic’n’Bob specifically — anyone who was on TV more than five minutes ago. We now have the first generation to be culturally cut off from its elders.

Over the past couple of years I have met twenty-somethings who have never heard of The Two Ronnies, of Only Fools and Horses, who have never seen an episode of Alan Partridge. A friend encountered a mid-twenties graduate (also Cambridge) who loves University Challenge but had never heard of Bamber Gascoigne. Another has a colleague, in a senior backroom position, who had never heard of Smashie and Nicey.

This isn’t an old fart despairing of young turks just because they’re different. Every generation enjoys new stuff — that’s how it should be. ‘Young blood must have its course, lad,’ as Charles Kingsley tells us. The problem is that for the first time ever the youngsters don’t know the context through which their blood is coursing.

When I was growing up in the 1980s I liked The Young Ones, Smith and Jones, Spitting Image. But I was aware of the stuff that had come before them. Sometimes the old timers made me laugh (Tony Hancock, Ronnie Barker), sometimes they didn’t (Tommy Cooper, Harry Secombe). What counted, though, was that I knew they were there, had some sense of what they’d been like. It helped define the modern programmes more clearly, made you appreciate how revolutionary they were. Indeed The Young Ones spelled out that rebellion, in the scene where Vyvyan ripped through a screen showing the opening credits of The Good Life, complaining that it was ‘so bloody NICE!’ (For the record, I loved both The Young Ones and The Good Life.)

How has it happened? Why do those born in the 1990s know nothing, as the Spanish waiter they won’t have heard of used to say? Simple — theirs is the first generation that has never been able to count its TV channels on one hand. They choose from a billion programmes on a million channels — or, increasingly, they shun channels altogether, consuming their content entirely on YouTube, hopping from one ‘if you liked this…’ recommendation to the next. We’ve known for a while that this is splintering twenty-somethings: they often love programmes their contemporaries have never heard of. Andy Warhol, as someone has pointed out, was wrong about the future — it’s not that we’ll all be famous for 15 minutes, it’s that we’ll all be famous to 15 people.

But what we hadn’t realised until now is that the new technology would also splinter the generations, putting a gap between today’s viewers and their predecessors. In the old days, television was a box that sat in the corner of the living room, and everyone watched the same thing on it. Even when cheap portables came along and teenagers could watch Channel 4 in their bedroom, they still saw what their parents were watching on BBC1 downstairs when they went past them to retrieve unhealthy snacks from the kitchen. Looking in the Radio Times to see when The Tube was on, you’d see the names Sid Little and Eddie Large. If you had any sense you wouldn’t watch them, but you knew the names. Now, however, everyone is in a different corner of the room, earphoned up to their own device, existing in separate universes. They’re all wonderful universes, and I like many of them myself. It’s just that I know how they’re linked to the universes that went before, but the young don’t. It’s sad that this sense of growth, development — and sometimes of outright rejection — has been lost.

There are also practical difficulties. Conversations are becoming harder, because of all those references people don’t get. Already I’ve had to retire my Roy Kinnear anecdote (a pity, because it’s an absolute belter). Pub quizzes are getting harder to write, too. I regularly used to ask a question to which the answer, when you pieced together the clues, was ‘Don’t tell him, Pike.’ That episode of Dad’s Army was first shown in 1829, and by law had to be repeated on BBC2 every Saturday at 6.30pm. So the question was a banker. You could rely on everyone in the pub being familiar with the line.

Not any more though. Never mind not knowing who Arthur Lowe is, the yoot don’t even know what a channel is. The TV set is on the dump, and history is out the window.