When Holst chose his titles and subtitles he was not indulging in the common form of program music in which a story is told or a scene depicted through sound. The few words he used for titles were meant as suggested characterizations: hints regarding what each musical movement embodied. In a letter to music critic Herbert Thompson, the composer asked him to bear in mind

The titles, then, were not intended as hints concerning mythological tales. However, by using the names of the planets, and in an order which suggests an outward journey into the unknown, Holst was able to prepare the listener in a certain way, to point the audience in the proper direction. Furthermore, his insistence on astrological cues, in spite of many reviewers' stress on an astronomical point of view, was a means of emphasizing the human aspect. Note that, in the letter to Thompson, Holst speaks of astrological significance, not the character of each planet.