But that’s what Britain in general and London in particular do. The city is essentially a tax haven with great theater, free museums and formidable dining. If you can demonstrate you have a residence in another country, you are taxed only on your British earnings.

And the savings on property taxes are phenomenal.

The property taxes on Mayor Michael R. Bloomberg’s $20 million London home come to £2,143.30 per year. That’s $3,430. Clearly, the mayor bought in at the right time. The Google executive chairman, Eric Schmidt, is reported to be house hunting here — he’s looking in the £30 million (about $48 million) price range. Yet he will pay a similar amount in property tax.

There are other facets of London real estate as a medium of exchange. British gross domestic product has yet to return to pre-crash levels, but the financial-services industry has roared back. Banks are paying out big bonuses again, and anyone looking for a safe investment is getting into London property.

From the top of Parliament Hill, on Hampstead Heath, look eastward. Out around the Olympic Park and beyond you see clumps of high-rise apartment buildings sprouting like toadstools in a meadow after a particularly heavy rain. These aren’t being built to meet the calamitous shortage of affordable family housing in the city; they are studio and one- or two-bedroom apartments. The developments are financed by “off plan” buying. Bonus babies look at the blueprints and put their money down with no intention of living in what they’ve bought — just collecting decades of rent.

And it’s not just those who work in London’s financial district, the City, who buy in. Hot money from China, Singapore, India and other countries with fast-growing economies and short traditions of good governance is pouring into London.

When I say property is money I mean it. An astonishing £83 billion worth of properties were purchased in 2012 with no financing — all cash purchases. That’s $133 billion.

I suppose the development that houses equals medium of exchange isn’t all bad. I have friends who were seriously successful “creatives” (architects, cinematographers, commercial and television directors, etc.) in their 30s and 40s. They bought houses when houses were places to live in. Once they turned 50, they passed through a mirror that turned them invisible. Work dried up. They have survived in London via the magic of remortgaging. They accept that their children will never be able to afford to stay on in the city.