"These rich bastards," said Ken Livingstone in a column in The Sun, "just don't get it." No one, he said, "should be allowed to vote in a British election, let alone sit in Parliament, unless they pay their full share of tax". We should, he said, "sweep away tax scams and everybody should pay tax at the same rate".

When he said this, he was probably thinking of people like the people who run Barclays bank. The people who run Barclays bank have just been told that they must pay half a billion pounds in tax they were trying to avoid, even though they'd signed a code saying they wouldn't. He probably wasn't thinking of people who used to be mayors of major world cities, who then went on to do things like host radio shows or advise Hugo Chavez. It's a shame he wasn't, because if he had, he might have thought that it wasn't always a good idea to talk about other people's tax arrangements if you didn't want them to talk about yours.

He might, for example, have thought that it might not be a good idea to make sure your earnings were paid into a company, rather than directly to you, so that if, for example, you earned £232,000 in 2009, and £284,000 in 2010, which is about 10 times as much as most people earn, you wouldn't have to pay tax at the normal rate. Instead, you could benefit from a special type of tax called "corporation tax", which is much less than the 50 per cent income tax rate you'd have to pay as someone who earned more than 150 grand PAYE. Which is, in fact, 20 per cent.

He might also have thought that if you were someone who said that they were very good with detail, and money, and budgets, then it might not be a good idea, when a journalist phoned to ask whether you had "engaged in any measures to reduce your tax burden", to say that you had "no idea". And then to say that you "seem to have paid an awful lot of tax". And particularly if you were hoping, in a couple of months, to be mayor of that major world city again.

He might, on the other hand, think that if you did say those things about tax, and someone found out about your own tax arrangements, there'd be a bit of fuss, but that the thing about fuss was that it usually went away. He might remember the fuss about the grants and pay-offs to people other people said were his "cronies". Or the fuss about the time he told two very rich Jewish businessmen that they could "go back to Iran". Or the fuss about the time he told a Jewish journalist that he was "just like a concentration camp guard".

He might even think that fuss was quite funny. That it didn't usually stop people liking him, and that it had certainly never stopped him from thinking that he was right. He might remember what he'd said in a recent interview, that it was "hard to think of a politician" who had "called it right" as often as he had. He might, as he thought that, give one of those smiles that made him look like one of his pet newts.

In this, the man who used to be mayor of London is very much like the man who's currently mayor of London, and who also wants to be mayor of London again. The current mayor of London, who's the only other politician in the country to be known by his first name, also doesn't seem to worry too much about fuss. He might remember the fuss about the woman called Petronella, and the fuss about the woman called Helen, and the fuss about Liverpool, and the fuss about the 250 grand he called "chicken feed" that he's paid for writing a column a week. He might remember that he had said that the allegations of phone hacking at News International were "a load of codswallop cooked up by the Labour Party". He might remember all of this, and think it didn't really matter, because nothing he ever said or did seemed to make people like him any less .

The man who used to be mayor of London was very, very keen on spending the taxes he doesn't seem so keen to pay. Last time he wanted to be mayor, he said that he would "defend" services against cuts. This time, he has said, as if there hadn't been any kind of financial crisis, that he will reverse cuts to the police force, and cut fares.

The man who's currently mayor has said he thinks it's important to be careful with taxpayers' money. He has said this, even though one of the first things he did, when he came into power, was get rid of the buses which the other mayor introduced, which cost an awful lot, and replace them with a different model. This week, he launched another new model, which cost £11.4m for eight.

If you don't live in London, you might think it doesn't really matter who wins the election in May. You might think it doesn't make much difference if London gets a very ambitious, very vain, very thick-skinned, very manipulative and strangely popular man called Boris as its mayor, or a very ambitious, very vain, very thick-skinned, very manipulative and strangely popular man called Ken. And maybe it doesn't. But those of us who do live in London can't help thinking that a city of eight million, which is also one of the greatest cities in the world, could do just a little bit better. And that whatever "corporation tax" might be, we'd quite like to pay it, too.

c.patterson@independent.co.uk; Twitter:@queenchristina_