Very few art-world figures can rival the powerhouse Hans Ulrich Obrist. Since his first show, famously held in his St Gallen kitchen in 1991, the Swiss curator has rarely left the airport, curating shows by the dozen, and relentlessly pushing the boundaries of the exhibition format: from the exhibition-as-a-bunch-of-instructions "Do It" in 1997, to the exhibition-as-a-time-based-spectacle "Il Tempo del Postino" with Philippe Parreno in 2007.

The co-director of exhibitions at London's Serpentine Gallery has also been conducting endless interviews with artists and thinkers of all kinds since his teenage years. Several of them are published in the "Interviews Volume 1 and 2" and the ongoing "Conversation Series." Yet for Obrist interviewing is more than a tool; it is an attitude towards life — one that perhaps culminated with the 24-hour "Interview Marathon" he conducted with Rem Koolhaas in 2006.

Obrist has just published an oral history of the architecture movement Metabolism in Japan together with Koolhaas, and only last week launched a new would-be movement, "posthastism," with Shumon Basar and Joseph Grima. In the pipeline — besides the supervision of the Serpentine Gallery extension in a nearby former munitions store — are another book on curating, an intimate show at the Lina Bo Bardi house in Brazil, and a "Brief History of Sound" book, as well as the touring of his "Agency for Unrealised Projects" to Berlin and of the "Indian Highway" show to Beijing. How does he do it?

Interviews are key in what Tino Seghal once described as your "quasi-Situationist mode of being." Why have your privileged this format over other more traditional forms of knowledge production, such as texts for example?

It depends on the moment. Since January, I've been trying to have this discipline of writing a text every week. There have been a lot of new texts, and obviously they are very often based on interviews. My great inspiration has always been Studs Terkel, who is a wonderful American oral historian. He was a radio DJ at first, interviewed a lot of jazz musicians, and at some point started to interview Americans about work. This became an amazing book about the Great Depression. He recorded something like 9,000 or 10,000 hours — infinitely more than I would ever record!

To record is a process against forgetting. I do interviews because it's what I've been doing every day for a few hours since I was a kid. I've always talked to artists. I met Gerhard Richter and Alighiero Boetti when I was a teenager, and I was really inspired by them. When Boetti died, I realized I only vaguely remembered so many things he told me. It was such a pity. Had I only recorded his voice, he would still be with me and I could listen to it from time to time. It was very painful not to have done this recording, and that's why I've tried to not let this happen again. Then it became formalized. I used to have conversations with artists and then I extended it to other fields. Curating is this kind of dialogue.

You've talked about the exhaustion of formats: the exhaustion of the biennial format, of the exhibition, or the conference format. Could we reach the exhaustion of the interview format? If the interview was to be reinvented, what could it become?

In some kind of way, the interview always goes in two directions. On the one hand it goes into depth, and on the other hand it goes into a broader reality. It goes into depth by speaking to people again and again. It can go on and on for many decades and you still have always a completely exciting, new conversation. That's the great thing about David Sylvester talking to Francis Bacon. These in-depth conversations are more vertical. Then, obviously, there are the more horizontal conversations, which is when an artist tells me about a scientist, an architect, a composer — that's this moment of going beyond the art world into other disciplines. When the vertical moment comes to a standstill, we make it horizontal again, it's a push and pull between those two. I think this is kind of infinite, but I need to think more about your question on the format being exhausted.

In English you say "two is company" and an interview is mostly two people in a room, or in a house. There are different possibilities to break open that format: to leave the room — we could now go on a walk — which I do quite often: interviews in a park, in a taxi, in a bus, on a plane. With Pierre Huygues, and also with Dan Graham, we did this thing where we would take a plane from A to B, or C to D. If the plane journey is four hours, you record four hours, if it's seven hours, you do a seven hours non-stop recording. That's a way of getting around. If that's stuck, you change the spatial circumstances. You can also test other kinds of temporalities: a conversation with someone for 24 hours, which I suppose leads to the marathon…

"Two is company, three is a crowd." One of the things I also do quite often in order to open an interview up: I would have a conversation with an artist or an architect again and again, and at some point we go together to see someone else. For example, Dominique Gonzalez-Foerster would say: "I'm fascinated by Enrique Vila-Matas, I would love to meet him." And we go and see him. Or with Rem Koolhaas, we go and speak to all the Metabolists.

In Japan.

These are trialogues: you go and see someone with someone else. And then obviously, you can go from there into the polyphony: if "two is company and three is a crowd," then the Metabolism project is the portrait of a movement. We were interested in this question: are there still movements in our time? That's also what the Manifesto Marathon addressed. At some point in the historic avant-gardes and in the neo avant-gardes there were all these movements from Dada to Fluxus, sometimes with a manifesto, sometimes without. In our times, when I speak to young artists, they have a lot of collaborations and dialogues but less movements — it's more atomized. Now obviously again there are movements, but they are more political movements, like Occupy Wall Street. That's interesting. Maybe they will happen in art as well. In the art world there aren't that many movements yet.

You mention Occupy Wall Street. We are in a paradigm-shifting period, or so one hopes. Do you feel that, in this society in crisis, the role of the artist is changing?

When I was a kid, and started to be obsessed by art in the 1980s, the art world was in this polarity Warhol/Beuys, Beuys/Warhol. Both expended the notion of art extremely but in very different ways. Beuys was co-founder of the Green Party, and for me, as a teenager, I was really interested in this idea of him being a political activist. Warhol extended the notion of art more within art itself, but Beuys was blurring art and life. Then Beuys died, and Warhol was hugely more influential over the last 20 years than Beuys. But one can observe right now younger artists connecting to Beuys, so that might be a partial answer to your question.

What is interesting right now is that these initiatives remain very often individual and you don't necessarily have movements. When we did the Manifesto Marathon, Tino Seghal was wondering if the movement with a manifesto was a very masculine, very loud thing — very 20th century. The 21st century is more about conversations.

In his talk at Tate Modern last week, Tino Sehgal talked a lot about slowness, and how it was a key aspect of the way he engages with the world in his work. As someone known for your hyper-productivity, how do you relate to this idea of slowness?

I'm interested in resisting the homogenization of time: so it's a matter of making it faster and slower. For art, slowness has always been very important. The experience of seeing art slows us down. Actually, we have just founded a movement with Shumon Basar and Joseph Grima last week called posthastism, where we go beyond haste. Joseph Grima was in Malta, and he had this sudden feeling of posthaste. Shumon and I picked up on it and we had a trialogue, which went on for a week on Blackberry messenger. Posthastism. [Reading from a sheet of paper hastily brought in by his research assistant] As Joseph said: "Periphery is the new epicenter," "post-Fordism is still hastism because it's immaterial hastism, which could lead now's posthastism." One more thing to quote is "delays are revolutions," which was a good exhibition title.

The beginning of my whole journey was night trains. It's a slow way of travelling and now we are working with Tino [Seghal] and Olafur [Eliasson] on solar airplanes. They fly at a hundred miles an hour, so it would be a little bit like travelling on a night train. Travelling might get slower again, if it's sustainable. All my shows have been conceived on night trains: the kitchen show, the hotel show, the Robert Walser museum, "Cloaca Maxima" in the drainage museum. I would take a night train and reflect on the conversations I've had with artists like Boetti or Fischli and Weiss and arrive in the next city. Somehow that night train rhythm was an idea factory.

You come back very often to your first show, held in your kitchen, with Christian Boltanski, Richard Wentworth, Fischli and Weiss. It has almost become a myth. How much of your story, which is repeated again and again, is a performance of your own artistic persona?

It is part of my biography and of my experience that I do these intimate exhibitions. I don't think it's necessarily about myth-making. Obviously, these shows do become rumors. Not that many people see them, but people tell each other about them. This also has a lot to do with early performance history, when seven people saw these performances and now they are world famous. That is a mechanism that is very key. But I also believe that artists produce other works when you invite them to do something else. The intimacy of the space makes them do work they wouldn't do in a big museum. For now we are working on the Lina Bo Bardi house in Brazil and for me it's an existential thing: I do need to do these shows. It's a sort of a fil rouge.

But do you see your obsessive curating as a performance itself?

I don't believe that the curator is an artist. I was very inspired by Harald Szeemann, who is obviously one of my great heroes. Harald had a signature, and things had to function within the signature of his exhibitions. He is the auteur, but that has never been my way to work. Everything in my shows is done by an artist. The more I can disappear, the less my signature is there, the better it is. Douglas Gordon will find the title, an artist will design the catalogue, Richard Hamilton will do the poster. If it is a performance, it's a performance that has always to do with someone else, or for someone else.

A performance of disappearance.

Something like that.