
“For the image of the sitter on the artist’s retina is passed on its way to the canvas through a mind chock full of other images; and is transferred-Heaven knows how changed already-by processes of line and curve, of blots of colour, and juxtaposition of light and shade belonging not merely to the artist himself, but to the artist’s whole school…and, in truth, a portrait gives the sitter’s temperament merged in the temperament of the painter.” from Vernon Lee’s Hortus Vitae: Essays on the Gardening of Life (1904)
Vernon Lee was the nom de plume of Violet Paget, a good friend of John Singer Sargent, who painted a lovely portrait of her that can be found online. She was an art historian, feminist, and pacifist (1856-1935).
Gilles Deleuze also noted, in his wonderful book on Francis Bacon, that the problem with beginning a painting is not that the canvas is blank, but that it is too full of everything that the artist has seen, which must be let go to begin a new piece.