ONE thing never questioned in a pub quiz is the pub quiz itself. Where did it come from? Who held the first one, and when? How has it become such a defining characteristic of British pub culture? Why do UK drinkers in particular seem to accept and enjoy challenges to their capacity for factual recall? What is the point?

No quizmaster would ask any of the above, because the answers are unknown, unverifiable or open to debate, and therefore unwelcome in those corners of the pub - and, by extension, the universe - where there can be no room for doubt. Here, there is only right or wrong, true or false. Over two nights, and two quizzes, at two of my local pubs, I decide to investigate the appeal of this peculiar social ritual from within, going so thoroughly undercover that even team-mates are soon impressed by the humourless, autocratic pedantry I bring to the competition.

At The Doublet on Glasgow's Park Road, proprietor Alistair Don doesn't even remember how long he has been shouting out questions of his own devising, without the benefit of a microphone, every Tuesday at 8.30pm. "Six or seven years, it must be," says Don. "More like 15," argues a regular from his barstool. "I told you to do it, remember? I said you should get a quiz going. It was all my idea." "Oh aye," says Don. "Maybe it has been that long, right enough. I'm getting f***ing cheesed off with doing it, but it brings in the punters."

Don could be speaking for pub landlords across the UK. I have boned up on the statistics and, according to the most recent annual market report by trade magazine The Publican, over 50% of licensed premises employ this form of "interactive entertainment", which is now second only to darts in that category. "The pub quiz is more popular than ever," says The Publican's Phil Mellows. "Traders are telling us that this activity is increasingly important to their business. They know they need to get people in every night, and they're aware that pub quizzes are an almost guaranteed means of doing that mid-week, when things are usually quiet."

In becoming a tradition within a tradition, quizzes may also be helping to preserve your community local. They are, statistically, much more of a constant in rural and suburban freehold pubs than city centre franchise bars, most of which operate a "no games" policy. But this does not explain why regular pub quiz contestants, who are otherwise unremarkable people, will fixate on winning a top prize of £25 in drinks vouchers as if it were the 13th labour of Hercules - less physically demanding, perhaps, than strangling a Cretan bull (which was, as the trivia-minded may know, the fourth of those labours) but no less worthy of Zeus's approval.

As The Doublet fills up, my companions and I must give serious thought to contriving a team name so clever and hilarious, yet apparently casual, that our rivals will be unnerved before the game even begins. Tastelessness and topicality are generally considered the winning combination in this regard, and Litvinenko's Dodgy Waiters is suggested, but I have already unilaterally decided on Quizteama Aguilera. This is plagiarism of sorts. I am hoping that nobody else in this saloon reads a newspaper column called Beta Male, written by London-based journalist Robert Crampton, in which he records the progress of his own quiz team, Sphynx, and the much better names chosen by their opponents.

"It's a pretty male thing, I think," Crampton told me earlier. "Three-quarters of the people who go to my quiz are blokes between 30 and 50, and that's probably true of pub quizzes in general. They might fulfil some primitive urge. Or maybe they're a way of taking stock, of saying, This is where I am in life, and this is what I know'. Personally, I get unaccountably annoyed when I can't dredge up the answer to something."

There are actually plenty of women in the competition tonight, and an all-female team ends up winning with a perfect score of 40 out of 40, but while the quiz is in progress I know exactly what Crampton means. Some questions are answered by Quizteama Aguilera, for right and wrong, through conferral between the members (every one of whom is a semi-bearded man of around 30 years old). We decide, collectively, that the colour of the cross on the Greek flag is blue. The answer, when it comes, is white, which sends an invisible Mexican wave of shame, recrimination and ludicrous mutual contempt through our ranks.

For a pursuit that seems founded on enlightened principles, pub quizzing can stimulate the least rational responses, and many of these feel wired to the male ego. Answering accurately, and single-handedly - What country controls the Panama Canal? That's a trick question! It's Panama! - makes me want to tear my T-shirt open and taunt everyone who got it wrong with the confrontational pinkness of my chest.

By contrast, when we are asked which drink was introduced to Europe by Dietrich Mateschitz in 1987, the sheer, despicable incorrectness of my guess (Kaliber: the right answer is Red Bull) makes me want to dash my brain out on the jukebox. Or at least the right side of that brain, with all its whimsy and intuition, which is plainly useless, and possibly even treacherous, in comparison to the mannishly reliable circuits of logic and reason that operate on the left.

Nonetheless, Quizteama Aguilera finishes in joint second place, winning £15, redeemable only in drinks from the bar. Rude as it may seem to reward our prize-winning mental faculties with an acid bath of alcohol, research shows that pub quiz contestants drink less, on average, than other patrons. Recent studies by Alcohol Focus Scotland led the Executive to recommend that more pubs introduce quizzes as one possible way of reducing binge drinking and associated violence.

"We don't think that pub quizzes will solve all our problems," says Gillian Bell of AFS. "But we are trying to encourage a change in the culture, and food, games, sport, even music can have an impact in making pubs something other than vertical drinking centres', where people just stand up and go through one pint after another."

The day after our Doublet semi-victory, I talk to Marcus Berkmann, author of key pub quiz texts Brain Men: A Passion To Compete and a lavish new compilation of questions from his own local, titled The Prince Of Wales (Highgate) Quiz Book. "As far as I've been able to find out," says Berkmann, "the pub quiz as we know it is about 30 years old. They don't seem to have existed before 1970 or so. Nor have they spread too far outside the British Isles, although they are a big deal with our overseas ex-pats and armed forces. And in my opinion the phenomenon really started with Trivial Pursuit."

Devised by Canadian journalists Chris Haney and Scott Abbott in 1979, the original matter-of-fact boardgame had sold in the millions worldwide by the mid-1980s, but according to Berkmann the British alone were gradually inclined to do without the board, the dice, and those ferociously contested coloured wedges (ancient arguments over Trivial Pursuit remain a source of irreparable estrangement in my family, and probably in yours).

"Uniquely," he says, "we got bored of everything except the questions. For us, the questions became the thing." But why? Berkmann is happy to agree with my own theory - that there is some subconscious historical link between Empire and empirical knowledge. Perhaps the British still cope with the vastness of the world, and the decline of their significance within it, through a command of hard facts, while the French, for example, seem happier to turn philosophical pirouettes in the airy realm of abstraction. "I do think it's partly a legacy of the way we're educated in the UK. As children, a vast amount of information is forced into our heads that we don't know is there until it comes out in a pub quiz 30 years later. And when that happens, it's a buzz." So specific is this buzz to England and Scotland that the artist Yara El-Sherbini has engaged in an ongoing nationwide experiment, co-sponsored by the BBC, which involves staging her own quizzes in pubs and more formal performance venues.

Her questions are "culturally loaded" into standard categories such as Entertainment and Pot Luck, and designed to engage contestants on a political level: name one movie, for example, in which an Arab was not shown as a banker, a belly dancer, or a billionaire? "In a pub environment," says El-Sherbini, "people can be taken aback by the more subjective questions, because there is no way of marking the answer right or wrong. There's a bit of tension, a bit of heckling. But the point is there is no single answer to some questions in life. I'm not trying to preach, I just want to bring certain issues to the fore, using the humour and fun of a pub quiz."

El-Sherbini's is a useful perspective - the supposed "fun" of a pub quiz is inversely proportional to how much you want to win it. I try to focus on that, not the £120 rollover jackpot, as Quizteama Aguilera prepare to compete in Dr Paul's Wednesday night pub quiz at Uisge Beatha. Paul Loughton himself has become a Glasgow folk figure in the 10 years he's been in business, and the breadth of his domain now extends to pubs all over the city. He employs a small taskforce of subordinate quizmasters (quiz-minions? quizzlings?), and will soon expand the business to specially-prepared packs so that barstaff can ask Dr Paul-brand questions of their customers even in his absence. He is a professional, and resents the suggestion that he is not a real doctor.

"I regard myself," says Loughton, "as a doctor of quizzology." In this respect, he is one of those rare people who is now doing what he dreamed of as a child. "Other kids wanted to be rock stars. I wanted to be a quiz master." His rise to power over the last decade has coincided with that of the internet, and Loughton believes the growing popularity of pub quizzes may be a reaction against that proliferation of information.

"There's a sense these days that with a computer in front of you, you can find out anything. But sitting in the pub, you're faced with the simple question: do you really know this? Maybe that challenge is more spicy now because it sucks you away from your internet connection, and lets you interact with actual people."

Dr Paul remains curiously impassive throughout (he models himself on "the greats Brucie, Leslie Crowther, William G Stewart they were always in control") but his quiz is funnier than most comedy shows. Straight sets of his "properly researched" trivia questions are interrupted by sudden snack giveaways, an eye-popping round of genuinely unprintable jokes, submitted by the crowd - which contains a high proportion of ironical students - and increasingly graphic and fantastical slanders against Phil Collins.

Quizteama Aguilera perform so magnificently that we are loudly booed and openly suspected of web-assisted phone cheating. We answer only one question incorrectly, guessing that Dr Paul's story of a Saudi citizen given 70 lashes for possession of chocolate liqueurs was false (No! True! Damn it!). But, somehow, a middle-aged, heavy-bellied and palpably drunk lone contestant called Bob is arbitrarily declared the winner after flailing his way through a final "dance-off". My hands reflexively contort themselves into vengeful claws for choking, but there is almost certainly a lesson in this. "Knowledge is one thing," says one team-mate, a wiser, better loser than I, "but it's no match for life experience."