You don't need to be young and foolish to suppose that when some pillar of Britain's financial establishment offers to lend you a heap of money it knows what it is doing and has reached an informed, professional opinion that you can repay it.
You would be wrong, of course. In real life the friendly fellow at the bank who signs off your loan stands to collect a bonus or commission for it. If he turns you down, he could quite possibly be penalised for missing his target. He is a salesman, selling money.
Hence the evidence of reckless lending piling up almost daily - record bankruptcies and voluntary settlements and bad debts shooting up at some banks conspicuously more than at others, all at a time of dirt-cheap interest rates and subdued unemployment.
Yet it has all been done without breaching the voluntary Banking Code, devised to keep the banks on the straight and narrow and ward off pushy regulation of their day-to-day activities by the Financial Services Authority.
Now, at least a year too late, the standards board set up to see the code achieves its purposes, is trying to put things right. It found banks lending people money to "consolidate" onerous debts they have run up with other lenders not bothering to check that they use the new money to clear their original borrowings. Others based lending decisions on a couple's joint income, while leaving one of the parties altogether in the dark about it.
This inquiry was limited to unsecured debt, so it didn't take in last year's wild mark eting campaign by
Barclaycard urging people to take out 25-year second mortgages to pay for a fancy car or holiday.
But it did find unsecured loans for such purposes stretching out over seven years.
So the code is being tightened up so that banks are expected to consider at least two aspects of affordability before they hand over the cash - this person's past financial behaviour, for instance, or references from employers or landlords, as well as the mysterious credit scoring process.
Pity no-one thought of that before.
* In 1970, services accounted for 53 per cent of Britain's economy, while 33 per cent came from manufacturing. Today it is 73 per cent and 16 per cent. The nature of the other 11 per cent eludes me.
Be that as may. The oddity is that all these years National Statistics has been publishing copious details of manufacturing output, but nothing on what is happening in the far bigger service economy.
That was because it is harder to measure and until yesterday NS was not confident that it could get enough of it right. Finally it has launched a new "services development" index.
Strangely, the joint second-biggest component of this index, level-pegging with education is called "letting of own dwellings".
Surely, buy-to-let has never taken off like that? It hasn't. This "letting" isn't letting at all. It consists of the notional rents that all mortgaged homes would command if they were let - which they aren't. Funny sort of service.