It is 9am, and the instructor, Matthias Pohm, begins with a challenge. "The new government has decreed that every German family must consume 20mg of hashish a week," he says. "Can you think of a suitable question to ask the government spokesman? For instance: why only 20mg?"
The pupils scratch their heads. "Will the cost be tax deductible?" asks the lady who during the week works as a tax inspector. "Can those allergic to hash take cocaine instead?" ventures a salesman.
The ice has been broken, the class is on a roll, everyone laughs. On to the next exercise. The participants are asked to write down the name of the person they hate most, catalogue two of their worst flaws, and construct a line of attack. This, after all, is a self-defence class. However, the weapons are exclusively verbal. The students are here to be kitted out with an armoury of one-liners, cheeky ripostes, biting sarcasm and devastating put-downs.
In a society where charm is for wimps, apology a sign of weakness and bullying an accepted form of behaviour, aggressive verbal skills are often deployed in everyday skirmishes. But doing it with wit - now that is ground-breaking stuff. Mr Pohm, one of five such teachers in the German- speaking world, knows he is playing with fire, and has been accused of dragging his people too fast into the humour equivalent of the nuclear age. "I am merely giving my students a weapon," he says. "How they use it is their business."
Mr Pohm, a 39-year-old former software engineer who changed to this field because he found communicating with machines somewhat limiting, is a man on a mission. "Perhaps there is not enough laughter in Germany," he says. "It is against that, that I'm fighting."
Sometimes, it is an uphill struggle. The first attempt at irony falls flat, as a student tries the unconventional in confronting her imaginary enemy: "Nora, don't you think you should be a little less arrogant?"
"Not quite there," the instructor declares.
The rest are not very funny, either. The bile pours, but true wit is in short supply.
Never mind. Mr Pohm has classified every kind of social atrocity, and devised the corresponding deterrent, or indeed counter-attack. All you need to do is learn them by heart, and practise to improve the speed of delivery.
After lunch, the teacher lets us into the secret of the "exaggerated response". Irony, he explains, is rare in Germany, self-irony practically unheard of.
Nineteen pairs of eyes widen. "What you do," Mr Pohm slowly explains, "is take on the criticism, amplify it and throw it straight back."
The lesson on self-deprecating humour proved to be The Independent's finest hour. "You never listen," came the mock charge. "What did you say?" whimpered your correspondent, to squeals of delight all round.
There were, roughly, a dozen different ways to disarm an aggressor with a quick one-liner which, this being the German language, can actually run to four lines, crowned inevitably by the verb at the end. It is worth waiting for, none the less. As the 19 participants spar with one another, one can detect in their eyes an intoxicating rush of adrenalin, a feeling of barriers being transcended by a mere curve of the lip.
It is five o'clock, time to put away the pens, retract those razor-sharp tongues, and face the bleak world outside. Mr Pohm exhorts his pupils to revise for half an hour three times a week, puts in a plugfor his book - two hundred pages of come-backs and double entendres - and the class is dismissed.
Dr Albrecht Bender, a patent lawyer who has just spent DM590 on his quantum leap to a new consciousness, is satisfied with the day's work. "It has been a very useful course," he says. "Now I must concentrate on the practical side of what I've learnt. I will revise, work slowly, and maybe, in three months' time, I will be ready to incorporate some of this into my personality."