More than any other art form, music in its essence manages to hide its meaning, while at the same time still producing in the listener a strong affect. On foot of this remarkable ability, music was hailed in the 19th century as the most important art form, a pronouncement for which Schopenhauer provided the philosophical basis. But music can also be seen as a language. Composers of music, with or without text, have techniques at their disposal, using all musical parameters, with which they can impart information which is non-musical and sometimes not even (unambiguously) expressed by the text. Opera composers such as Mozart, Verdi and Wagner used musical means to underline, expose or contradict situations or feelings of characters that might be consciously or unconsciously hidden. In some cases, the music may be interpreted as “body language”. Depicting unconsciously hidden feelings, music shows similarity with the dream from a Freudian viewpoint. Music also seems to depict hidden “truth” in symbolic, and thus veiled, form. While not always straightforward, it is nonetheless necessary in psychological interpretations of opera characters to differentiate, just as in literary fiction, between utterances ascribed by the composer to a character and those that he ascribes to an omniscient.