He is a man in his early 30s who lived in London before and has been working in the Frankfurt financial services industry for a few years now. Asked about the difference between the two, he took me to a pub called Mutter Ernst in the Alte Rothofstraße at the edge of the financial district.
We are literally standing in the shadow of a huge Commerzbank office, Germany's biggest bank after Deutsche Bank (insiders just say Deutsche). Around the corner are JP Morgan, Credit Suisse and Royal Bank of Scotland. It's six o'clock in the evening and the Rothofstraße is deserted. Inside Mutter Ernst (Mother Serious) it's very peaceful and placid, with a few people here and there eating their Frankfurter or sipping an Apfelwein.
"In London at this hour this place would be jammed. Frankfurt has the best Opera in Germany and fantastic concerts, all generously funded by local taxes. But there's none of that 'lads' culture you find in London."
Regulars of the banking blog know that the financial industry does not look kindly on those who speak to the press, so I cannot tell you much more about my interviewee, except he is not German himself. This is another difference between London and Frankfurt; there are far fewer people in any one particular niche, making it even harder to hide their identity.
So here we go, big differences between London and Frankfurt, and it'd be great if other insiders could add their own thoughts in the comment thread. Asked for an analogy, he says that Frankfurt is like London's younger, not so boisterous cousin. Younger or older?
"Hmm, in the 15th century Frankfurt was already a centre for trade finance. So you might say older. But this place never had London's big bang of deregulation. So when it comes to today's banking, Frankfurt is late to the game."
Also, he says, finance in Frankfurt is more knitted into the wider fabric of the economy. "Finance here is less of an end in itself."
"It's not like German bankers sit together and say: 'let's be modest'. You have the same tendencies at work here as in London. But German bankers operate in a different environment, and the financial lobby here just doesn't have the political weight it has in London.
"It gets less of what it wants. The financial transaction tax is a vote-loser in the UK. Here it's a winner. The majority in Germany feel that bankers should pay more.
"Generally I'd say German culture is more egalitarian than the UK, more risk-averse, and slightly quieter. You are right that German banks loaded up on risky exotic products in the US like no other, but that was probably out of naivety, not a thirst for risk.
"They just didn't understand these things. The people who ran the smaller German banks that got burnt so badly were used to a culture where trust builds long-term relationships. But when you can cross the border, you cannot assume that your counterpart shares those values. Same story with German banks lending to southern Europe."
Having said all this, he confirms that the stereotype of Frankfurters in the rest of Germany is that they are arrogant and ostentatious.
"The Goethestraße around the corner is one long row of luxury boutiques. And there are a hell of a lot of Porsches in this city."
• Next: where is the anger?
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image: © Konrad Hädener