The cycle of fugues is introduced and concluded by a Praeludium and Postludium, the second formed by turning the Praeludium upside down and reading it backwards. In solving technical problems he posed himself, Hindemith created awork of considerable imagination. Intellectual achievement and sheer delight in playing are shown not to be mutually exclusive. The Ludus is a graphic example of the composer 's delight in the fantastic. He illustrated the workwith colored pencil, drawing a lion for each entry of the subject of the fugues. And for each of the twelve, a different kind of lion according to the character of the music, providing an instructive formal analysis of the music.