After Mandela what will happen to South Africa?
"All hell will break loose," said the voice on the radio.
It was a call-in show - on a topic that is on many minds here these days: the fate of a 94-year-old man lying in a hospital bed in Pretoria, and the fate of South Africa once he is gone.
For years people here have been understandably reluctant to discuss the death of Nelson Mandela - out of a profound respect for the man who, more than any other, steered this country from apartheid to democracy.
But the passage of time, and the health scares of recent months - have nudged the issue away from the shadows.
The man on the radio was a black South African from a poor township, and he was articulating a belief that has gained a small level of currency here: that Mr Mandela's passing will unleash not just grief and nostalgia, but a violent rage against the poverty and inequality that still exists here, two decades after the end of white minority rule.
There is, certainly, anger in the country.
From Our Own Correspondent
- Insight and analysis from BBC correspondents, journalists and writers from around the world
- Broadcast on Radio 4 and BBC World Service
Recent headlines have highlighted violent industrial action, the massacre at the Marikana mine, the death of a man dragged behind a police van and the enduringly high crime statistics.
The theory goes that - even from his hospital bed - Mr Mandela exerts some sort of restraint on a turbulent nation, almost a decade after he retired from public life.
It is a theory most South Africans find - quite rightly - both offensive and absurd.
The next two callers on the radio show said as much.
Imagine Britain in the mid-1960s still anxious about the broader implications of Winston Churchill's failing health.
No, in almost every way South Africa is already well into the post-Mandela era.
Other presidents have come and gone.
And yet the jitters here speak to a broader theme - of a grand, miraculous nation aware it is poised to close a defining chapter in its history.
There are not many heroes left these days, so people cling to Mr Mandela like a precious relic.
And they cling too to the sense of drama, of high stakes, that characterised those years, in the late 1980s and early 1990s, when South Africa really did stand on the precipice - the dangers of a racial civil war, of total collapse - were raw and real.
Today's headlines can still leave you speechless - the corruption allegations that cling to President Jacob Zuma, the extraordinary levels of sexual violence.'Stop looking back'
There is a new crisis here every week.
The South African writer, Rian Malan, put it well a few years ago, when he tried to explain to a foreign audience why he could not imagine living anywhere else.
"You don't understand. It's boring where you are," he wrote.
Yet, when you peer behind some of the headlines, things can seem less dramatic.
Take Oscar Pistorius.
Yes, he shot his girlfriend dead. Perhaps he was afraid of burglars.
You could see it all as another sign that a violent country is going to the dogs or you could marvel at the huge new Pretoria estate the athlete lived in, surrounded by other huge new middle class suburbs, where race is no longer such a big deal, and younger South Africans worry more about their mobile phones than about what life will be like after Mr Mandela.
The drive from Mr Pistorius' home to Johannesburg is an eye-opener. In the space of a few years the two cities have essentially merged. For the whole 40-minute drive new business parks and suburbs line the motorway.
It was perhaps fitting that a senior government minister chose this week - with Mr Mandela still in hospital - to declare a decisive break with the past.
We must stop "looking over our shoulder, we are responsible ourselves", said the Planning Minister Trevor Manuel.
He urged a gathering of civil servants to stop blaming apartheid for everything that was still going wrong in South Africa.
It was time to deliver.
The scars of apartheid are still real here. They will not be easily shrugged off.
Inequality endures and the economy is not growing anywhere near as fast as it needs to, unlike so many other corners of this continent.
But as South Africa waits to hear news, good or bad, about Nelson Mandela it is slowly coming to terms with the fact that its heroic years are over.
It may still be a dramatic, exciting, scary place.
But it is becoming ordinary too.
How to listen to From Our Own Correspondent:
BBC Radio 4: A 30-minute programme on Saturdays, 11:30 BST.
Second 30-minute programme on Thursdays, 11:00 BST (some weeks only).
BBC World Service:
Hear daily 10-minute editions Monday to Friday, repeated through the day, also available to listen online.