"Cultural Leadership," he says.

"Are you a typical Cultural Leader?" I ask him.

"Yes," he says.

Cultural Leadership: "These [highly fastidious] people are a.s.sured, secure and very discriminating. They spend their abundant wealth very carefully. They value the privacy of their homes and home life.

It doesn't sound like any credit-card companies will be bombarding Professor Webber's home with junk. Mosaic's lifestyle data (Professor Webber writes the text himself) is often really quite impolite. For instance, when people within the category known as "Welfare Borderlines" purchase cosmetics, they are "likely to be striking accessories rather than means for displaying natural beauty." The professor has, however, been most glowing about his own people, the Cultural Leaders.

I TELL BRUNO and Professor Webber about Richard Cullen's suicide. I suggest that families like the Cullens are bombarded with junk because the direct-marketing departments of the lenders are guided by Mosaic pointers such as: "likely to be interested in adverts for financial products ... keen to take advantage of easy credit," and ACORN pointers like "educated to a low degree." In the mathematical world of the credit industry's computer lifestyle calculations, it strikes me that a consensus had been formed about the Cullens. The family needed the money, but because they owned their own home, there was something to seize if need be. And they weren't smart enough to read the small print and spot the trap they were being beckoned into.

For a moment Bruno seems unsure how to respond to this. My impression is that he doesn't want to downplay Mosaic's significance, but neither does he want to admit that his company's computer program played a role-however peripheral-in a suicide. So he shrugs and says, yes, some credit-card companies use Mosaic, but they use their own files too.

Before I met Professor Webber, I fancifully imagined him as a Caractacus Potts, a madcap inventor filled with sorrow at how the private sector had hijacked his brilliant machine. But when I ask him if he's alarmed by any of Mosaic's current uses, he says the opposite is true. He wishes the public sector were efficient enough to use Mosaic more.

"Our country," he says, "would be better organized if they did."

But this is beginning to change, says Bruno. For example, TV Licensing are using Mosaic to choose which areas to target with their vans.

MY LASTING MEMORY of my afternoon at Experian is Professor Webber and I, a Cultural Leader and a Global Connector, sitting inside these mysterious former MI5 headquarters in the heart of Mayfair, imperiously scrutinizing, via a computer slideshow, Welfare Borderlines.

As we looked at the slides I asked Professor Webber if he considered himself an academic, but he laughed scornfully and said he was a taxonomist. He said, "I like putting things into categories. Taxonomy is less authoritarian than academia."

But Mosaic is packed with the professor's opinions and judgments-a subjective mind-set that is guiding countless credit-card companies and leading to Happy Families being swamped with offers of easy credit.

Of course, Bruno was right that no company will rely solely on Mosaic-but the computer program is surely indicative of the way things are done inside the whirring, mathematical, computer world of credit-card marketing.

"You've probably got enough for a book," said Bruno as I left that afternoon, which I presume was his way of saying, "Don't call me again."

ACCORDING TO THE National Consumer Council, one in five people are borrowing money just to pay household bills, and one in four are struggling to meet their repayments. Half a million people in Britain have "crippling debts on their credit cards."

Advice services such as Debt Free Direct-who try to help people like Richard Cullen-say they received 275 percent more calls per day in December 2004 than they did a year earlier. A quarter of those in debt are receiving treatment for stress, depression, and anxiety. Britain's bailiffs are enjoying 70 percent more work than they did two years ago.

Wendy Cullen is annoyed with Debt Free Direct. In the weeks before her husband's suicide, he phoned them countless times for help; but, she says, "They did sod all, excuse my language. They'd phone back and say, 'He hasn't sent us the right information.' And I'd reply, 'I saw him send the right information.'"

Wendy says that had Debt Free Direct been more helpful, her husband would be alive today.

I CALL ANDREW REDMOND of Debt Free Direct. He says they're required by law "to get all this verification. The creditors want proof that the person in question cannot afford to pay more than they say they can afford." Andrew says they've been fighting this for years.

"This," he says, "is a cla.s.sic example of a case when a simplification of the process might have averted a tragedy. We had several conversations with Richard Cullen, and we offered the best advice that we could, but it was too little too late."

Debt Free Direct have transcripts of all the conversations between them and Richard Cullen. In these transcripts-they say-you can read his continual pleas for help. And then you can read the advisers' responses-that they can only help if he can provide this verification, and then that verification, and then the last transcript is the phone call from Christopher Cullen saying that Richard has been found dead.

These days, only 40 percent of calls made to debt-advice centers are answered. Sixty percent of the time the centers are so busy, the phone just rings and rings.

I PHONE BARCLAYS to see if someone will talk to me about Richard Cullen.

"I don't think anyone will comment on this at all," says the first press officer I speak to. "Someone will get back to you but I really don't think this is something we'll be able to help you with."

I ask the second press officer if there's anything to be learned from Richard Cullen's suicide. He says, "We did lend to Richard Cullen. That was clearly a poor decision. We should have shared data better within the bank. We did get it wrong with Richard Cullen. But we have learned from this. We are now sharing data better within the bank."

Is Mosaic used within Barclays as a way to target certain people with junk?

"It is true to say that Mosaic and systems like Mosaic are used by the direct-marketing departments to make our marketing as efficient as possible," he replies. "We want to get as few pieces of paper out as possible with the most number of responses. That is the very specific area in which we do use Mosaic-to target people who are likely to respond to direct mail."

"And Mosaic pointers like 'keen to take advantage of easy credit'?" I say.

"Yeah, we would see those as pointers," he says. "However, this doesn't mean that the credit-card companies will be willing to lend to that customer. Because we mail to someone in no way suggests that we are willing to lend to that person."

The third Barclays press officer I speak to says the problem with Richard Cullen was that at the time he didn't seem to be in trouble. He was making his repayments. What n.o.body knew-he says-was he was achieving this by borrowing on other cards.

"Richard Cullen should have asked for help," he says.

Of course, he asked for help, repeatedly, with Debt Free Direct. But they were required by the creditors to make Richard Cullen jump through such complex hoops that they just couldn't help him in time.

I CALL WENDY CULLEN to see if there's any news. She says things are bad. Some credit-card companies have written off the debts, for the sake of good public relations, but others haven't. Morgan Stanley and the RBS, in particular, are being worryingly silent, she says. Wendy's house, and her 500 car, and the trailer, remain at risk.

Just before I phoned, Wendy opened a letter from the credit-card company MBNA. She a.s.sumed it was about the debts. Richard had three MBNA cards and sheets of MBNA credit-card checks, which he used to pay his Goldfish minimum repayments. Wendy knows this because she found the stubs stuffed behind the washing machine a few days ago when it was pulled out for repairs. There they were, in Richard Cullen's neat handwriting: "G/Fish 172.53." And so on.

But the letter she received from MBNA today was something different. It read:

Dear Mr. Cullen

Let's face it most of us encounter financial problems at some stage in our lives. All it takes sometimes is a little bit of bad luck.

The letter goes on to offer Richard Cullen, who has now been dead for three months, a 15,000 loan. ("10.9 percent APR variable. Loans are secured on residential property.")

"Just imagine," the letter concludes, "this could give you a much needed light at the end of that dark tunnel."

In 2004, MBNA's profits were one and a half times that of McDonald's.

THE CULLENS are beginning to piece together the minutiae of the mess Richard got himself into. They've found credit-card statements stuffed in drawers and behind wardrobes all over the house. Wendy says I can come down and look at them.

While I'm sitting there, I hear a key in the front door. It is Christopher.