The performance of my Piano Concerto with Bruno Walter, in Paris in 1928, was a pleasure, the more so for being unanticipated. I had not expected this ‘Romantiker’ from another era to be able to count my scrambled meters, or, knowing his habit of slowing down for the second subject of a symphony, expected him to keep my metronomic tempi. Yet he followed me as nimbly as anyone with whom I ever played the piece.