Can comedy change the way we think? These days, it's hard to see how. Observational comedy, particularly of the do-you-know-what-I-hate variety, goes from strength to strength; each year, a new batch of comics arrive in Edinburgh complaining about their love lives and wondering why it is they always end up with odd socks.
"It's so predictable," protests Scott Capurro. "I get so bored by what I see in live performance. These guys just want you to know that they're straight. I mean, stand-up isn't the most macho of occupations, is it? That's why they go on about their girlfriends all the time."
Yet the San Francisco comic believes that comedy has a potential to alter attitudes, even though his own shows have been known to alienate audience members. His remarks at last year's festival about the Holocaust ("Holocaust Schmolocaust. Can't they find something else to whine about?") prompted people to walk out of his show. Likewise, his suggestion that one man watching the show should "die of Aids" prompted a flood of outraged letters to newspapers, and numerous disquisitions on what should and shouldn't be laughed at. "Comedy should challenge people," he maintains. "There are no rules. Of course I love that there's been an extreme response to my work. Some people said it was the best thing they had ever seen, others cried 'He's evil'. At least I'm moving them in some way."
But Capurro wants it to be known that his material isn't just about getting a reaction. "As I said in the show, black people can talk about white people but white people can't talk about black people," he says. "It's insane. I want to shatter that and open up the comic boundaries of what we can talk about. I want to break the taboos."
Certainly, where this comic is concerned, nothing and no one is sacred. In the past Diana, Princess of Wales, the Queen Mother, Oprah Winfrey, and Christopher Reeves ("only in a wheelchair does he finally command the screen") have all been at the sharp end of his tongue. He has trawled all manner of nefarious subjects, from phone sex and cocaine to paedophilia, disability and euthanasia. Naturally, he is unrepentant about last year's Holocaust remarks, though you do get the feeling that things went a lot further than he had anticipated.
"I certainly had no intention of scaring people and making them cry," he says. "I wanted to cover material that I hadn't covered before and that no one else had either. That's the point of Edinburgh, to push the envelope. If it works, or if it doesn't, it's got to be good that I tried."
Given that Capurro is himself Jewish, he could plead personal experience as a defence. Certainly, a comic's relationship to their material is important – Francesca Martinez, a comic who was born with cerebral palsy, made headlines last year with gags about how she walks in a straight line when she's drunk. But where Martinez is self-deprecating, Scott Capurro is unflinchingly provocative.
"Listen, I've got plenty of material about air-travel if you want to hear it," he says, rolling his eyes skywards. "I've been there when stewardesses have been on their cellphones, and when they've forgotten to shut the emergency door. But I don't want to do air-travel jokes. It's the most tired, overdone subject. I don't want to talk about how different men and women are, or how much I hate my partner's domestic habits. I don't want to patronise an audience in that way."
Before he was a comic, Capurro was an actor – you may have seen him in Mrs Doubtfire, helping Robin Williams turn into a woman. But those days are long gone, he says. "I didn't like the audition process. I can't stand being told I'm too old, too young, too tall or too short. That's why I never moved to LA. Anyway, writing is so exciting for me. Sitting alone in a room is the best thing for me. I guess I was a weird child – I was very isolated and read a lot."
Capurro's near-the-knuckle material isn't just confined to stand-up. His first book, Fowl Play, the story of a closeted comic, was well received over here but remains unpublished in the States, having been deemed too risqué for publication. Then there's his second, as yet unpublished book, a spoof of the musical Rent, entitled Runt, which revolves around a heterosexual man who writes a Broadway musical about Aids. When he hears that the gay community is planning a picket, he decides to "come out" as a homosexual man with HIV.
Contrary to popular belief, Capurro is immensely likeable. He's also strangely naive about the impact of his work. He says that he can't understand why television channels are wary of him. In Melbourne, he was accused by one television director of "polluting minds".
His reception over here as been no less frosty. "The BBC are terrified of me – they're afraid that I'm a loose cannon. It's become this handed-down rumour that I upset people. I just don't get it."
Perhaps they heard about his latest Edinburgh show. It's a play about the unconscious relationships between gay men and their dads, called – wait for it – Fucking Our Fathers. There's one scene in particular that will lodge in your mind – the one where Capurro is having sex with a rent boy and wondering which celebrity he looks like. Didn't he at least consider toning down the title?
"No, really I didn't," he replies brightly. "First it was called Dating Our Fathers. But this alliteration was so much better. You know, the writing's pretty mild. Really mild, actually. But I really don't care that much. I want to do what I want to do. I'm not going to clean up my act just so that I can get on television."
Scott Capurro is at The Scotsman Assembly, Assembly Rooms, Venue 3 (0131-226 2428), to 27 August, midnight (01.10)Reuse content