“.. Your Lordship [Dartmouth], I am sure, will be sensible of the dress thus far, but I defy any but a painter of some sagacity (and such you see I am, my Lord) to be well aware of the different effects which one part of a picture has upon another, and how the eye may be cheated as to the appearance of size, &c., by an artful management of the accompaniments. A tune may be so confused by a false bass that if it is ever so plain, simple, and full of meaning it shall become a jumble of nonsense, and just so shall a handsome face be overset by a fictitious bundle of trumpery of the foolish painter's own inventing.... Lady Dartmouth's [second/repainted] picture will look more like and not so large when dressed properly..”

In a letter to the Duke Alfonso of Ferrara, From Venice, April 1, 1518; as quoted by J.A.Y. Crowe & G.B. Cavalcaselle in Titian his life and times - With some account ..., publisher John Murray, London, 1877, p. 181-82
1510-1540

Letter to Edward Seymour, Lord Protector (28 January 1549), quoted in Leah Marcus, Janel Mueller and Mary Rose (eds.), Elizabeth I: Collected Works (The University of Chicago Press, 2002), p. 24.

Lectures XIV and XV, "The Value of Saintliness"
1900s, The Varieties of Religious Experience (1902)
Context: I am well aware of how anarchic much of what I say may sound. Expressing myself thus abstractly and briefly, I may seem to despair of the very notion of truth. But I beseech you to reserve your judgment until we see it applied to the details which lie before us. I do indeed disbelieve that we or any other mortal men can attain on a given day to absolutely incorrigible and unimprovable truth about such matters of fact as those with which religions deal. But I reject this dogmatic ideal not out of a perverse delight in intellectual instability. I am no lover of disorder and doubt as such. Rather do I fear to lose truth by this pretension to possess it already wholly.

In a letter from Auvers, Summer of 1890, to Theo (found on him on 29 July, after Vincent had shot himself); as quoted in Vincent van Gogh, edited by Alfred H. Barr; Museum of Modern Art, New York, 1935 https://www.moma.org/documents/moma_catalogue_1996_300061887.pdf, (letter 652 ) p. 7
1890s

Quote from Mondrian's letter to H. P. Bremmer, Paris 29 January 1914; ; as cited in Mondrian, - The Art of Destruction, Carel Blotkamp, Reaktion Books LTD. London 2001, p. 81
1910's

Thackeray, Ch. 9

Variant translation: Close your bodily eye, that you may see your picture first with the eye of the spirit. Then bring to light what you have seen in the darkness, that its effect may work back, from without to within.
Quoted in The Romantic Imagination: Literature and Art in England and Germany (1996) by Fredrick Berwick and Jürgn Klein, and in "Culture: Caspar D. Friedrich and the Wasteland" by Gjermund E. Jansen in Bits of News (3 March 2005) http://www.bitsofnews.com/content/view/154/42/
undated
Context: Close your bodily eye, so that you may see your picture first with the spiritual eye. Then bring to the light of day that which you have seen in the darkness so that it may react upon others from the outside inwards. A picture must not be invented but felt. Observe the form exactly, both the smallest and the large and do not separate the small from the large, but rather the trivial from the important.

Life Without Principle (1863)

Goupil and Co.
Quote in his letter to brother Theo from The Hague, The Netherlands (13 December 1872); as quoted in Vincent van Gogh, edited by Alfred H. Barr; Museum of Modern Art, New York, 1935 https://www.moma.org/documents/moma_catalogue_1996_300061887.pdf, p. 17 (letter 2)
Vincent's profession then was picture dealer at Goupil and Co., with branches a. o. in The Hague, London and Paris
1870s