Now Fischer is in Hong Kong, at the Gagosian Gallery, for his first solo exhibition in Asia. As its title consists of musical notes wobbling along a four-lined (not the usual five) staff, you’ll just have to hear it in your head as a brief, off-key impossibility. Before we meet, I spend some time reading up about Fischer, whose work I’ve never seen in real life, and I compile a list of specific little questions but, really, they could all be cast into one big one: how much of this is a joke?

“Urs” means “bear” in German and Fischer is, indeed, ursine. (He once worked as a nightclub bouncer.) Read his name sufficiently often and it starts to conjure up a separate, National Geographic identity – that of a bear, standing in some icy river, catching salmon with its paw. (When I tell him this later, there is a gleam of pleased amusement at the thought, but he says, not wishing to indulge himself, “In these grizzly movies, the bears look sad.”)

Fischer, 43, doesn’t look sad. He looks contentedly rumpled and a stranger to the more metrosexual trimmings of 21st-century man; when the photographer arrives, he runs a hand through his hair as a concession to the process, and unabashedly points out the stain on his front (breakfast). The visual impact he’s most concerned about doesn’t include his own.

At the same time, he gives off a strong sense of looking; you might think that’s barely worth the comment but in these self-regarding, celebrity days, when the artist has become the icon, it’s not to be taken for granted. While being photographed, he says, “See there, a little tree in the window” and points to a plant, many windows higher, in the adjoining block; he’s fascinated by the Gagosian’s feng shui crystals on the windowsill; he comments on the colours of others’ clothing against his work.

Such prompting has a contagious effect. The cover of Shovel in a Hole (2009), a book of essays on his work, depicts him with eyes shut, cuddling his dog, Layla, in the crook of his (extensively tattooed) arm. Look closely, and it becomes apparent that the dog’s open eyes are actually Fischer’s, vigilantly Photoshopped in. After a while, trotting round in his company, seeing what he sees, I begin to understand what that transferred canine-vision feels like.

We stroll through the gallery, circumnavigating the security guards. (A human instinct to touch the work is an ongoing issue.) Fischer, like most artists, isn’t keen on retrospective analysis. “I don’t usually come back to a show,” he says. “I try not to think about it. If you make it, you can’t look with the same eyes as someone else. It’s like parents – they have delusional images of their children.” As long as he’s working on some­thing, it has potential. “And once it is – it is.”

His exhibition history can sometimes suggest that what it is is really a method of tormenting galleries and curators. The 2007 You crater-exhibit, for example, took 10 days of excavation and, apparently, cost Gavin Brown about US$250,000. In 2009, while he was preparing his first New York museum show, at the New Museum of Contemporary Art, The New Yorker magazine charted his artistic process. One of the central works in that show was going to be a bed. It then became a horse. In the final straight, the horse morphed into two crutches, cast in aluminium.

“It’s kind of the same as the horse, because it’s very leggy,” Fischer explained to the magazine. “The crutches will com­municate with each other.” He also wanted the gallery’s third-floor ceiling to be lowered. “In this last month I have thought a couple of times of killing him,” the exhibition curator, Massimiliano Gioni, was wearily quoted as saying.

Naturally I wonder if he intended to inflict similar torture on the Gagosian, in Hong Kong, but he has been relatively restrained.

“I put in this wall,” he says, indicating one near the entrance. “People go to the same space and so it’s good to bring in a fresh view.” And although the 11 “tableaux” – neither exactly paintings nor photographs – in the show are large (about 250cm by 300cm), they aren’t going to threaten the Pedder Building’s listed foundations.

They’re thematically problematic, however – which is to say they’re a continuation of Fischer’s Problem Paintings series, which he began in 2011 when he took old stock photos of Hollywood stars and stuck silkscreened images of fruit, vegetables and tools on top. These new works are photo­graphs of brushstrokes that have been digitally mani­pu­lated and silkscreened over interiors of Fischer’s studio and home so you can’t quite tell what you’re looking at: foreground? background?

I’d seen some images in advance that, frankly, left me unmoved (if you don’t count eye-rolling). Now Fischer begins to talk about how the works are hung, how he’d planned their placement inside a miniature model of the Hong Kong gallery in his Brooklyn studio, then rejigged them when he saw how they looked together on his arrival.

“I do a lot of different things, in different media, in differ­ent types and forms – different families of images – and you have to bring each thing to a point where it can function. You push each one far enough until it has a life of its own.” He adds, “It’s very exact.”

How exact? “OK,” he says; and he begins to talk, with unexpected passion and seriousness, about each piece. “In the background, these are moments, little collages, of life,” he states of partially glimpsed interior details – a table, a cushion featuring an image of Sophia Loren, his own works, the works of friends. “These are all found moments in my life, not staged reality.”

With the layers of paint, printed on silkscreen, he adds movement, colour, texture.

“Paint is liberated from being a painting,” he explains. “It’s more like a process.” As he describes the waves of paint – “a sea that crashes in ... it’s like thoughts and feelings, they have a special way of how they move” – the works do, indeed, begin to take on a life of their own. A few visitors pass, with little delay, through the gallery: there’s a strong temptation to invite them to stop and listen through Fischer’s eyes.

Standing in a corner of the second room, I look back at a work, Kumquat Tree 2017, on the wall of the first room. Maybe it’s the angle of the light but it’s become, astonishingly, lovely – a swirl of greens and blues. (The note I write as a reminder simply says, “I see more beauty.”) It’s framed twice: once by its own mount, once by the gap in the specially made wall in between. Did he envisage that double effect in Brooklyn?

“Sure!” he says. “You always see two shows – when you come in and when you go out. You have a turning point, a pivot point of the show.”

A few minutes later he remarks, “Basically, I find a way every painting is as happy as can be. This work suffers if you don’t see it from far away.” When I say that it doesn’t sound as if he’s let it go yet, he replies, “You can still hold things in your mind.”

In the back office at the Gagosian, Fischer potters about for a while, checking everything out like a curious child. He flicks through gallery catalogues on the work of Zeng Fanzhi, and then the late Austrian artist Franz West, who created unlikely, interactive pieces and was a strong influence. (“This is closer to me.”) Fischer’s easy, occasionally illuminating, company. One of his best-known works, offi­cially called Untitled (Lamp/Bear) (2005-06), is of a seven-metre-high bronze teddy bear with a light attached to its head that he’s said to have based on his own teddy bear; but it’s not a stretch to view it as a sly self-portrait.

Why doesn’t the show have a title?

“There is a title!” he protests, mildly. “I picked something that depicts music but I didn’t want a specific melody. There’s a big limitation in language ... words can be too harsh.”

Having been born in Zurich, the words he grew up speaking were Swiss German ones.

“It’s all dialect, dialect,” he says. “German is a foreign language.” His parents were doctors, and he has an older sister who became a journalist. He didn’t attend art school – he studied photography at Zurich’s Schule für Gestaltung (“design school”) but dropped out and went to live in Amsterdam in 1993 – and perhaps this is why he remarks now, “I still think it’s weird to be an artist. I’m an artist! It doesn’t mean that I totally know what that means.”

The artistic designation he usually gives himself is “sculptor”. He’s a good carpenter – his father taught him Swiss craftsmanship – and in his early years in the Netherlands, he made film sets. By definition, those tend to have a short lifespan. Much of his subsequent output – the waxwork figures melting into shapelessness or the pieces deliberately created from unfired clay to ensure that they’ll disintegrate – shares that impermanence.

Sometimes he seeks outside destructive assistance. In February, at Sadie Coles HQ, in London, he invited guests to remould his plasticine replica of Rodin’s The Kiss; it was mutilated. (The frenzy was partly attributed to Brexit, which was being voted on in the House of Commons that night.) In fact, you could argue that the most abiding artworks in his life are the tattoos, which he began to collect as a student in Switzerland. He says he got the last one “about 15 years ago – it’s a young person’s thing”. One day, of course, that body of work will be gone, too.

He was 33 when he moved to New York, in 2006. A year later, You brought him attention.

“I wanted to do a show where there was less than you might see before. And the way to do that is take it out.” He hesitates. “If you really want to make it boring – it’s a sculptural problem. You can add or deduct as a basic mode of operation.”

At the time, New York magazine thought part of the crater’s achievement was that you – and You – could be in two contradictory places at once. (“You are indoors and outdoors; there are the perfect white walls of the gallery and this red-brown New York earth.”) The review also read it as a warning against the conventional – specifically the lure of bigger dealers. It noted that previous Gavin Brown artists, including the Chapman Brothers, had moved on to the Gagosian.

A decade later, in the Gagosian, Fischer contemplates the contradictory aspect of this ascent. “I started very early with shows, at 21,” he says. “I mainly worked with a gallery in Switzerland for the first six or seven years, a slow start to ease in. And then all of a sudden, yes, things change ... Art always was a weird thing. In European history, it was used to decorate palaces or a church or a state, to represent power. But one thing I do like – it’s a pretty good refuge for all kinds of people, from high to low. Not many other worlds I’m aware of have a mix of people so broad.”

In his Brooklyn studio, he usually has 12 or 15 assistants, most of them on a long-standing freelance basis.

“I like it if they have their own time, it’s exhausting to be in someone else’s life. If they get grumpy, it comes back to me.” Does he get grumpy? Fischer grins. “I can do. Then people keep their distance.”

Everything stops for studio lunch, however, prepared by his personal chef, Mina Stone. Food is so important to him that Fischer has published a book of her mostly Greek-influenced recipes called Cooking for Artists (2015). The preparation of food is another ephemeral activity; pinning it on the page, however, at least gives it a life into the beyond.

“Art books you look at a few times – then, what can you do? But cookbooks unfold in a different way. It’s good for me to do that, to find a voice outside.”

Publishing, as he observes, is a tough business, although presumably he’s not exactly short of money. His Untitled (Lamp/Bear), for example, exists in three editions. In 2011, a yellow version – having occupied the same Seagram Building spot where Big Clay#4 would be deposited in 2015 – was sold at Christie’s for US$6.8 million, reputedly to a member of the Qatari royal family. It’s currently on display at Doha’s international airport.

“Everything I make, I put back into something – into the studio, into production,” he says. In this financial context he also mentions, briefly, his exes. He has been married three times; by his second marriage, he has a daughter, Lotti, aged seven. Leaving aside parental delusion, he speaks of her painting ability solely as a function of her age: “I think it’s beautiful, it’s art as celebration of life not as illustration of thought.”

That will vanish, too. Critics often refer to his work’s humour but what you take away is his focus: the bear stolidly waiting for a fleeting glimpse in the water. So ... how much of his work is a joke?

“None of it. But if people perceive it that way, it doesn’t matter. It’s a comfort to put things in a certain place to assert control. For example, I made the house out of bread. In Austria, they said it’s about the body of Christ. In the US, it’s about gluten.”

We both grin. Perhaps the viewing public is the true joker. What’s it about for him?

“Where I grew up, bread is the core of everything.” Under his breath he adds, once more, utterly serious, “It’s not a joke.”

Urs Fischer’s exhibition will be on display at the Gagosian Gallery, 7/F, Pedder Building, 12 Pedder Street, Central, until May 13.