“There are always clouds in the international sky. You never get a perfectly blue sky in foreign affairs. And there are clouds even now. But we feel confident that the common sense, the patience, the good-will, the forbearance which enabled us to solve greater and more difficult and more urgent problems last year will enable us to pull through these difficulties at the present moment.”

in interview with nl:Ischa Meyer, c. 1988
quote c. 1988 - from ('RM'), 157; p. 41
Karel Appel, a gesture of colour' (1992/2009)

Source: Practical Pictorial Photography, 1898, Composition and clouds considered as an aid to expression, p. 105

Ann Curry (September 22, 2004) "Painter Bob Ross remains an iconic figure years after his death", NBC News.
Attributed

Source: House Rules

the washed-out, almost invisible blue of a hot, summer noon; the soft robin's egg, sometimes almost greenish blue of a late springtime evening, the darker, almost violet blue of fall. I have become a connoisseur of the coloring that the leaves take on in autumn and I know all the voices and the moods of the woods and river valley. I have, in a measure, entered into communion with nature, and in this wise have followed in the footsteps of Red Cloud and his people, although I am sure that their understanding and their emotions are more fine-tuned than mine are. I have seen, however, the roll of seasons, the birth and death of leaves, the glitter of the stars on more nights than I can number and from all this as from nothing else I have gained a sense of a purpose and an orderliness which it does not seem to me can have stemmed from accident alone.
It seems to me, thinking of it, that there must be some universal plan which set in motion the orbiting of the electrons about the nucleus and the slower, more majestic orbit of the galaxies about one another to the very edge of space. There is a plan, it seems to me, that reaches out of the electron to the rim of the universe and what this plan may be or how it came about is beyond my feeble intellect. But if we are looking for something on which to pin our faith — and, indeed, our hope — the plan might well be it. I think we have thought too small and have been too afraid...
Ch 24
A Choice of Gods (1972)

Source: Life of Pythagoras, Ch. 1 : Importance of the Subject
Context: Since wise people are in the habit of invoking the divinities at the beginning of any philosophic consideration, this is all the more necessary on studying that one which is justly named after the divine Pythagoras. Inasmuch as it emanated from the divinities it could not be apprehended without their inspiration and assistance. Besides, its beauty and majesty so surpasses human capacity, that it cannot be comprehended in one glance. Gradually only can some details of it be mastered when, under divine guidance we approach the subject with a quiet mind. Having therefore invoked the divine guidance, and adapted ourselves and our style to the divine circumstances, we shall acquiesce in all the suggestions that come to us. Therefore we shall not begin with any excuses for the long neglect of this sect, nor by any explanations about its having been concealed by foreign disciplines, or mystic symbols, nor insist that it has been obscured by false and spurious writings, nor make apologies for any special hindrances to its progress. For us it is sufficient that this is the will of the Gods, which all enable us to undertake tasks even more arduous than these. Having thus acknowledged our primary submission to the divinities, our secondary devotion shall be to the prince and father of this philosophy as a leader.

Diary-note of Boudin, 3 December, 1856; as cited in the description of his painting 'Sky, Setting Sun, Bushes in Foreground' http://www.muma-lehavre.fr/en/collections/artworks-in-context/eugene-boudin/boudin-skies, by the Muma-museum, Le Havre
A quote from Boudin's personal diary sheds remarkable light on a small group of his sky studies
1850s - 1870s

short notation, 1881: from 'Notes inedites de Seurat sur Delacroix', in 'Bulletin de la Vie Artistique', April 1922; as quoted by John Rewald, in Georges Seurat', a monograph https://ia800607.us.archive.org/23/items/georges00rewa/georges00rewa.pdf; Wittenborn and Compagny, New York, 1943. p. 6 - note 9
Seurat studied carefully the paintings of Eugene Delacroix, and wrote in 1881 about Delacroix's painting 'The Fanatics of Tangier' https://upload.wikimedia.org/wikipedia/commons/a/a0/Eug%C3%A8ne_Delacroix_-_The_Fanatics_of_Tangier_-_WGA06195.jpg this notation
Quotes, 1881 - 1890