it is certainly best to separate an artist from his work so completely that he cannot be taken as seriously as his work.
 Friedrich Nietzsche, On the Genealogy of Morality (1887). copy citation

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Author Friedrich Nietzsche
Source On the Genealogy of Morality
Topic work artist
Date 1887
Language English
Reference
Note Translated by Horace B. Samuel
Weblink https://en.wikisource.org/wiki/The_Genealogy_of_Morals

Context

“in the melancholy, cramped, and embarrassed lucubrations of his later years, there are a hundred places in which there are manifestations of a secret wish and will, a despondent, uncertain, unavowed will to preach actual retrogression, conversion, Christianity, mediaevalism, and to say to his disciples, "All is vanity! Seek salvation elsewhere!" Even the "blood of the Redeemer" is once invoked. 4. Let me speak out my mind in a case like this, which has many painful elements—and it is a typical case: it is certainly best to separate an artist from his work so completely that he cannot be taken as seriously as his work. He is after all merely the presupposition of his work, the womb, the soil, in certain cases the dung and manure, on which and out of which it grows—and consequently, in most cases, something that must be forgotten if the work itself is to be enjoyed.” source