"All art is artifice, and therefore no work of art is sincere. Once we become conscious of a feeling and attempt to make a corresponding form, we are engaged in an ac? tivity which, far from being sincere, is prepared (as any artist if he is "sincere" will tell you) to moderate the feeling to fit the form. The artist's feeling for form is stronger than a formless feeling. Art is the definition, the delimitation, of feeling. To quote a powerful image of Stravinsky's (in The Poetics of Music) the lava is already cold by the time it has assumed a form. When we recognize feeling in a work of art, it is not the artist's feeling: it is our own feeling transferred to a ready form. A work of art is a feeling in-formed."
January 1, 1970
https://en.wikiquote.org/wiki/Sincerity