Richard Wagner in Bayreuth by Friedrich Nietzsche

All those to whom the thought of Wagner's development as a man may have caused pain will find it both restful and healing to reflect upon what he was as an artist, and to observe how his ability and daring attained to such a high degree of independence. If art mean only the faculty of communicating to others what one has oneself experienced, and if every work of art confutes itself which does not succeed in making itself understood, then Wagner's greatness as an artist would certainly lie in the almost demoniacal power of his nature to communicate with others, to express itself in all languages at once, and to make known its most intimate and personal experience with the greatest amount of distinctness possible. His appearance in the history of art resembles nothing so much as a volcanic eruption of the united artistic faculties of Nature herself, after mankind had grown to regard the practice of a special art as a necessary rule.

It is therefore a somewhat moot point whether he ought to be classified as a poet, a painter, or a musician, even using each these words in its widest sense, or whether a new word ought not to be invented in order to describe him.