So when it comes to London architecture, Gough and Piano are chalk and cheese, Little and Large. Also David and Goliath, because Gough’s connections mean he wields more power than might at first appear. Piano knows little of Gough, but he knows plenty about English Heritage. “They said my building may be good but, if so, that it might detract attention from St. Paul’s Cathedral. What can you do? The only answer to that kind of criticism is to kill yourself. I love St. Paul’s. But what is wrong about loving something of your own time as well?”

Piano believes that London Bridge, with all its public transport connections, is one of the few ideal places for a car-free, low-energy, high-transparency London skyscraper of the kind he plans. Although he has built other skyscrapers in Berlin and Sydney, and has designed another for the New York Times in Manhattan - the first new tower proposed in that city since September 11 - tall is not necessarily always the urban answer, he says. He is in the midst of designing a second London project, a big low-rise commercial development behind Centre Point in New Oxford Street. “All I know is that cities must be dense,” he says. “Whether you go tall or whether you go broad is not really the issue. I think that London is one of the few cities in the world that can be easily densified.”

Gough, I suspect, would not disagree with Piano on the density issue, only on the means to achieving it. Of his own work, he says: “We have our pleasures. We put a high level of intensity into enriching the average environment.” But you don’t hire Piano for that kind of work. The truth is, this is not an either-or situation. London needs original infill buildings, and it needs excellent landmark buildings. It needs the high intelligence of both Gough and Piano. And it still needs a taller skyscraper.