P iotr Anderszewski frowns down at his hands and says:

"I'm on an eternal search for the perfect city. It is one of my main preoccupations. I want a place where I can live and also a place that I can leave. Even the most beautiful city isn't right if you feel trapped." The 45-year-old Polish-Hungarian pianist recently moved to Lisbon, which he says suits him because it is full of travellers like him. "It's about the food, the architecture, the light... There's a lot of water around and the light is luminous. I like it there, for now."

In music as in life, Anderszewski is a man who takes his decision-making seriously. His recitals are intense and wonderful: he is a profound communicator, a meticulous craftsman, a deeply original interpreter. He infuses every gesture with tremendous care; no phrase is thrown away, no nuance without meaning. The process of putting together such acutely considered performances is painstaking and lengthy, he tells me, which goes some way to explaining why his repertoire includes just a handful of core composers.

One of those composers is his Polish compatriot Karol Szymanowski, whose miniature triptych Metopes features in Anderszewski's recital at the Edinburgh International Festival this Friday. "With Szymanowski especially it is about trying to execute precisely and concretely what is written on the page," Anderszewski says. "Sometimes that process is dull and painful, sometimes it feels soulless, but I can't see any other way. There is so much going on in every measure and you just have to basically figure out how you are going to do it with your ten fingers." He moves his fingers around to demonstrate: "You know, which finger will be put where, how it's going to work sound-wise. Only by trying to resolve the problems of craftmanship will the craftmanship eventually disappear and the right interpretative strand become clear."

I ask whether some of this finicky investigative work could be done through listening to recordings or reading scores away from the piano, but he shakes his head: too easy, he says. "Listening is passive, but when I talk about concrete work I mean something active. Nobody else is going to do this work for me. I wish I could delegate and give half of my fee to some assistant..." Like a sous-chef who does all the chopping? He smiles and nods: he is passionate about food and the cooking analogy seems to amuse him.

"But no," he continues, serious again, "playing the piano is such a delicate balance between your thoughts and spirit and a physical world. It goes both ways. The spirit can help overcome technical problems, but working hard on a technical problem can also bring you into the spirit of the music on a level that you hadn't reached before."

Anderszewski's performances are often described as meticulous, but he is reluctant to accept that quality about his playing. "The thing is, I am lazy by nature," he says. "Therefore if I decide to take something on I have to make sure that I do it to the end." And by "doing it to the end" he means committing a great deal of time to incorporating a new work into his repertoire. Learning has always been a slow process, he says: "Taking on a piece is a huge enterprise, maybe because of that natural laziness. I always have to start from zero, almost as though I am learning the piano from the beginning each time. It's like a completely blank canvas, and that takes time. It's not the easiest. I wish I was faster. I used to be insecure about it. When I see my colleagues learning the complete Beethoven sonatas one month then all five concertos the next month..." He pauses and runs his hands through his hair.

"Look, for me it's such a big thing to learn one piece, let alone the complete 32 or something. I finally finished learning Bach's First English Suite just a couple of weeks ago. I can't tell you what agony it was to get it into my system. It's almost like a foreign body that has to enter me and will ultimately become part of me. I absorb it to the extent that it becomes part of me and I become part of it."

Where, then, does the act of performance fit in? How can such a deeply interior relationship between man and music withstand the public platform, let alone translate to it?

Anderszewski sighs and shakes out his hands. "That is almost a different job," he replies. "I spend months alone in a room creating an entity between the piece, me and the piano, then I go on stage and try to make a performance out of this entity. It can be quite violent, the clash between those two worlds. But I do love communicating things. I have an urge to share what I feel about a piece. If I didn't, I could never do what I do."

Piotr Anderszewski plays at the Queen's Hall, Edinburgh, on August 15