The first of Debussy's "Childrens Corner" The title of the alludes to Muzio Clementi's collection of instructional piano pieces, Gradus ad Parnassum ("Steps to Parnassus"). The "Gradus ad Parnassum" was one of the most frequently-used exercise books in France at the time, similar in sound to the Czerny exercises such as the "School of Velocity". In the middle, the pianist slows down and tries his material in other keys for exercise. Doctor Gradus Ad Parnassum is of intermediate difficulty.