"That's right. And the time when Cortot came to Vienna in 1947 remains one of my greatest pianistic memories. He came there to play for the first time after the War, and we all knew what the war had been for him, what his ideological engagement had been. Cortot played two programs. The first part of the first recital, how shall I say this... it was an absolute disaster. Cortot played Chopin's Fantasy, which is not very difficult from a technical point of view, but he didn't manage to play even one octave correctly. Jörg Demus was seated next to me, and he was seething: "My goodness, how is this possible? He's an amateur, I'm leaving at intermission!" After the intermission, however, Cortot came back on stage like a changed man. It was a different man, a different pianist. He had gotten ahold of himself. I couldn't believe how well he played the Sonata Op. 35 No. 2, which is such a perilous piece by comparison. At the end of the concert, with Gulda, we found Demus and tried to convince him that he had missed a major event: "That's impossible! I don't believe you – and I already sold my ticket for the second recital!" [laughs] In the end, we weren't able to convince him. A week later, in front of a sold-out house, with all three of us in attendance, Cortot played the 24 Preludes and the Kreisleriana. I can tell you that he went far beyond, in terms of depth, poetry, and spontaneity, all the recordings he had ever made of these pieces, which we knew so well. It was a revelation! It was so moving! All the pianists who were there agreed. When Cortot and Fischer were on the right foot, it was perfect, in terms of the cleanness of their playing, and not just from an emotional or spiritual point of view..."
January 1, 1970
https://en.wikiquote.org/wiki/Alfred_Cortot