Robert Taub is a distinguished Beethoven scholar, a world-famous performer, and - following in the footsteps of T S Eliot - the second artist in residence at Princeton University's Institute for Advanced Study.
But his attention one rainy afternoon last month was all about the genius of Jelly Roll Morton and Fats Waller.
'What happiness! What piano playing!' said the 39-year-old pianist, due to play in Hong Kong on Sunday night, as the opening performance of this year's four-day International Piano Festival.
'I used to play jazz on trumpet, and when I listen to Fats Waller, I know what real joy is.' Peculiarly, this is the same Robert Taub who can sit down in the cafeteria of the institute and, with equal enthusiasm, give the most fascinating look at his own field of international recognition, one Ludwig Von Beethoven.
Why Beethoven? 'Because of the immediacy of the passion and emotion,' Taub said, carefully spooning down a tuna salad. 'There's such a wealth of sound, wealth of expression.' And were these riches actually generated by Beethoven's deafness? As an answer, Taub described the background of the 'Appassionata' Sonata, which he will play at City Hall.
'This was the most agonising time in Beethoven's career. He knew he was growing deaf - which is the worst thing that can happen to any composer.