Aaron Copland & Halsey Stevens: SymphoniesOn April 15, 1931, the Dance Symphony, written by a young composer, Aaron Copland, whose talents were nevertheless very striking and whose name was becoming familiar to a vast segment of the American musical world, received its first performance by the Philadelphia Orchestra under the direction of Leopold Stokowski. Turning to the music page, readers of the next mornings Philadelphia Record discovered the provocative banner: HISSES AND PRAISE GREET