When a picture is sold, the matter becomes a question of honesty. The artist who sells a picture, knowing that it is painted with colors which will fade or otherwise change, is guilty of the same kind of dishonesty as that of the merchant who misrepresents the quality of his goods. If it be granted that it is both foolish and dishonest to neglect the proper consideration of this, to the painter, most important subject, the materials of his craft, it is certainly the part of wisdom for him to learn something of the nature of these materials. The subject is one not unattended with difficulties. Colors which are entirely and undoubtedly permanent, are after all comparatively rare. The discovery of a new one is hailed with delight by chemists, we can not, alas, say by the artistic fraternity, as artists are too generally indifferent to the question or permanence, caring only for brilliant effects in the present and regardless of any changes time may bring.
M. Louise McLaughlin, Painting in Oil: A Manual for the Use of Students, (Robert Clarke & Co., Cincinnati, 1888), p. 61.
The bad fabrication of the materials used by artists is an acknowledged fact, and the idea of remedy is beginning to become general; to-day this question is considered, and yesterday it was thought good form to ignore it. On all sides symptoms manifest themselves of an approaching reaction against ignorance; we see coming a psychological evolution which shall lead painters no longer to blush at knowing their business; and the moment is not far off when a gentleman who shall say in a drawing-room "I do not care what becomes of my pictures after they are sold," will be thought as pretentious and as ridiculous as would be an architect if he made light of the solidity of the monuments entrusted to him to construct.
J.G. Vibert, The Science of Painting, (Percy Young, London, 1892), p. 161.