But what would London look like without TfL’s regulations and licenses? A real world example of an all-but-free taxi market can be found in that renowned hub of capitalist free-marketeering, Tehran. In the Iranian capital, any car is a potential taxi and anybody who wants to pick up a passenger does.

There are 22,000 black cabs in London and another 49,000 vehicles licensed for private hire. Some 30,000 licensed taxis operate in Tehran. But so do an estimated 53,000 unlicensed taxis—though this number is extremely fluid. The result is not A Clockwork Orange-type world of widespread sexual attacks, armed robbery and societal breakdown as foretold by TfL. Instead, getting from place to place in Tehran is remarkably easy, safe and cheap.

In the absence of formal structures, a sophisticated eco-system of cab options has emerged. Commuters can call a taxi to the door or flag one down on the street to godar baste (literally, “closed door”), hiring the whole cab for themselves. Or they can walk to the nearest main road and, at any point on the street, jump into one of the passing shared taxis that ply fixed routes up and down that particular street or between major city squares. These shared taxis form a city-wide hub-and-spoke network. Unlicensed cabs look like normal cars, but move slowly as they look for fares, flash their lights at waiting commuters and tend to have the window open just a crack so people can shout their destination at them.

Driving a fixed route obviates the need for drivers to know the roads or reading maps. Unlicensed drivers tend to prefer these routes (which is not to say they cannot be found for longer routes and more complicated journeys). This system complements the city’s public transport system, which includes a metro with three lines, scores of buses routes and the inevitable motorcycle taxis.

The result is that commuters rarely have to hang around. Taxis do not to disappear during rush hour, as they tend to do on London, but seem to multiply. Supply also expands to accommodate demand at night when people head home.

Taxis are also remarkably cheap. This is not only a result of Iran’s cheap petrol prices. Drivers get a fixed monthly quota of 60 litres of subsidised fuel per month. Anything over that must be bought at a significantly higher price on the open market. What is more, one of the benefits of owning a taxi license is a higher fuel quota. This keeps prices of  licensed taxis in check.