Relaxed after a meal at Scott’s – his favourite London restaurant for 40 years –  and smoking his favourite brand of Havana cigar (‘banned in America, of course’), Rubinstein chatted to me for an hour and a half with an irresistible blend of reminiscence and fun. At 81 – and with the twinkle in his eye and fingers totally undimmed – he is something of a phenomenon. Yet he makes no particular effort to stay young. He does with very little sleep, eats what he likes, drinks three cups of coffee before going to sleep, and can travel further and for longer periods than his much younger wife. ‘I never take naps, never go to a spa, smoke large cigars – in fact, I do all the silly things I always did – even go to three movies one after the other’.

Perhaps the continuing freshness of his playing can be accounted for by his own dictum: ‘I see my role at this late hour as trying to play a little better what I used to play a little less well’. And today he confines himself to those works in which he feels he has something to offer that younger players may not have. It was not always so. ‘I used to be what I call an “on-my-knees musician”. I would play anything and everything. I learnt Bach’s B minor Mass, all Wagner, most of the symphonic repertoire, and the accompaniments, in piano arrangements, for violin concertos. I did all the chamber music repertory, accompanied singers in Schubert, Wolf, Debussy, playing for artists like Maggie Teyte. I lived every kind of music and I didn’t have much patience with the piano virtuosi who spent six hours playing Clementi and all kinds of difficult exercises every day to perfect their technique. They were martyrs, I thought. I liked to enjoy life, see pictures, go to plays – I once spent two weeks in secret going to Stanislavsky productions in Moscow. And my playing was like that of a bad pupil – I hadn’t enough respect for it.

‘Then in 1933, when I was well over 40, I married, and my wife persuaded me to use my capital of talent. I suddenly found it was right to practice – and I think I can say I transformed myself into a decent pianist. But, even at 81, I still think there’s so much to improve and, by golly, I want to do it – although I’ve told my family to shoot me if I go on too long. It’s sad when people have to say “too bad, but you should have heard him 20 years ago”.’

Joachim, who with three bankers paid for his musical education, was one of the main influences on his early years. ‘He was a great one for sight-reading and from the beginning I used to accompany his violin pupils in anything and everything’.

The two pianists he most admired in his youth were Eugen D’Albert – ‘I was most impressed by his Beethoven concertos’ – and a Frenchman called Eduard Risler (whom, Grove relates, played all the Beethoven sonatas in London in 1906). ‘I was impressed by Schnabel’s intellect but I worshipped Risler’s playing. When he interpreted Beethoven, it seemed like his language. He had a deep, inborn feeling for the music – there was nothing contrived or clever about his readings. I remember on one occasion he played the second movement of Schumann’s G minor Sonata and afterwards everyone was crying. He ennobled me – one felt like a good and grateful listener at a great happening’.

Any idea that Rubinstein has just come to chamber music is very much disproved by the facts as he told me them. ‘I was always buried in chamber music. I used to play sonatas before the First World War with the wonderful Polish violinist Paul Kochanski and trios with him and his brother. Then during that war I often played with Ysaÿe, with Casals, with Thibaud, with Tertis. That was in London where many artists were exiled. We used to have midnight sessions going on until dawn just playing for our own enjoyment. Once I remember someone jokingly asking Thibaud whether he would play the Bach Chaconne at seven in the morning. He took out his violin and there on the doorstep while we were waiting for a taxi, he played it.

‘Of course, as your success as a soloist grows, managers and impressarios are reluctant to let you play with others. But I did manage to play with the Pro Arte Quartet in the 1930s, and now I can impose my own plans and likings. Besides, the Guarneri is a wonderfully fresh and un-routine ensemble’.

His London debut was with Casals at the Queen’s Hall in 1910, when he also gave three recitals at the Wigmore Hall. By that time he had already broken away from the child prodigy image. But it was his famous series of concerts in Spain during 1916 that established him beyond doubt, he considers, as a solo pianist. ‘They told me I was the only one who could really play Spanish music. From then on, I had to play it so much that I became tired of it. I remember on one occasion an English society lady of rather more wealth than intelligence asking me to play some “Ramon Navarro”  – she’d got her film stars and composers a little mixed’.

It was perhaps records more than anything else that established his true fame in this country and for that we have to thank Fred Gaisberg, but before coming to him, Rubinstein told me about the first attempt to get him on disc. ‘During my first tour in the US after the First World War I was in love with the mezzo-soprano Gabriella Besanzoni – what a marvellous Carmen she was. I wasn’t very popular yet in America – they said I played too many wrong notes – but she was, and Victor tried to bribe me to get her for them – I was her sort of unpaid agent – on the understanding that “we might have a spot for you”. I wasn’t interested as pre-electric records made the piano sound like a banjo.

‘Then, one day shortly after the advent of electric recording Fred Gaisberg took me to lunch at Hayes. After the meal, he simply asked me to sit down and play whatever I liked. I chose the Chopin Barcarolle which, unbeknown to me, Gaisberg recorded. When I heard the test pressing, I fell in love with it and that disc was my first to be issued. I’ve recorded the piece four or five times since but never so well, I think. Then, of course we followed it up. I suppose my records of Tchaikovsky’s B flat minor Concerto with the LSO and Barbirolli did more than anything to establish me in America as a serious pianist in the late 1930s. Now I suppose I’m quite well-established’ – this, with a little smile – ‘as a recording artist. Two years ago I was the classical best-seller in America together with the Philadelphia Orchestra. I’m glad that they have come over to RCA so that we can get together at last. In fact we shall soon record Chopin’s F minor Concerto, I hope, and his Fantasy on Polish Themes.’

Has he a favourite record? ‘Really, the last one I have made. I’m never satisfied with the older ones – I always dream of doing them again – better. In the same way, every concert is just a lesson for the next. But I love making records. I’m always struck with terror when I hear the first take but in a few minutes I realise where the tempo is wrong, where I’m too loud, or too sentimental so I can get it right the next time. Mind you sometimes I don’t succeed in achieving what I want. There are tapes of Schubert’s late sonatas and of the Schumann Fantasy. They’re in the can, as they say, but I find them artificial and laboured; the right spirit is not there. Then I’ve done the three Brahms quartets with the Guarneri and these were successful, I think.’

Rubinstein hates comparing work against work as to their respective quality. ‘I believe they are just different, not minor, deeper or longer. One can’t say whether Rembrandt or Titian is the better painter. In the same way when I play a Liszt Rhapsody or Faure’s Quartet, for that moment this is the only kind of music and I’m not thinking of Beethoven or Brahms. I’m completely involved in the work in hand and just then nothing else matters. In the same way when I eat a Crêpe Suzette, I’m not thinking of the Steak Béarnaise I ate before.’

The good-food analogy is typical of this urbane, well-travelled cosmopolitan. He speaks eight languages ‘but I would give seven of them away if I could really dominate one. I spoke two languages as a boy. We spoke Polish at home, but as Poland was subjugated by the Tsars and we were treated like underlings, Russian was the official language in my schools. When I went to study in Berlin I learnt German quickly. As I already knew Yiddish from home, I picked it up quickly. Joachim persuaded me to have French and English lessons so that when I eventually went to Paris and London, I soon knew these languages reasonably well. I think the Russian artists who come to the West today are very much handicapped by not being able to speak other languages.’

He has little general advice for young players. He abhors all methods – ‘we are all so different’  – and considers it essential for teachers to understand the psychology of their pupils so they can learn what they can and what they cannot achieve. ‘We are all so different and what one can do, another can’t. I no longer play Bartók or Prokofiev because these can be done just as well by the young pianists. It’s only interesting for me to play music these days where I can offer something of my own that perhaps others have not got.’