City memories go back to the days when its banks had no regulators — or none, specifically, with the force of law behind them. Instead, they were supervised and monitored by the Bank of England, and the Bank was the arbiter of credit, which was and is their lifeblood. All this worked, so far as it did, because the Bank was at the centre of the markets and uniquely well informed.

Since then supervision has made way for regulation, and one Act of Parliament has made way for another, with a sixth and seventh now in prospect. 

By now it must be plain that more and tighter rules are not enough, and may be a standing temptation to push each rule to its limits. What has been missing — the ingredient without which no reformed system can work — is effective information. 

The Bank, from its place at the top of the pyramid, ought to be able to see and hear what is happening, but will have to work at it. The City's markets have changed, its place within them has changed, and the years of focusing on the inflation rate have served as a distraction. All those economists will need to get out more, and to take their line from Housman. 

A critic, so he tells them, has to deal with the frailties and aberrations of the human heart, which are not susceptible of hard-and-fast rules. This truth is what governs a critical dog in its search for fleas: "They require to be treated as individuals." Bankers, too.