“Propriety is that perfection of style which comes when a work is authoritatively constructed on approved principles. It arises from prescription, from usage, or from nature.”
Source: De architectura (The Ten Books On Architecture) (~ 15BC), Book I, Chapter II, Sec. 5
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Vitruvius 203
Roman writer, architect and engineer -80–-15 BCRelated quotes

Letter to John Adams (27 November 1775)
Context: I am more and more convinced that man is a dangerous creature; and that power, whether vested in many or a few, is ever grasping, and, like the grave, cries, “Give, give!” The great fish swallow up the small; and he who is most strenuous for the rights of the people, when vested with power, is as eager after the prerogatives of government. You tell me of degrees of perfection to which human nature is capable of arriving, and I believe it, but at the same time lament that our admiration should arise from the scarcity of the instances.

Delacroix, quoted by Paul Signac: in D'Eugene Delacroix au Neo-impressionnisme, Chap. I.; 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.10 + note 15
Quotes, undated

Source: The Principles of Agriculture, 1844, Section I: The fundamental principles, p. 3.

“The principles of ethics come from our own nature as social, reasoning beings.”
Source: The Expanding Circle: Ethics, Evolution, and Moral Progress (1981), Chapter 6, A New Understanding Of Ethics, p. 149

Philosophy and Religion 1804)

Vous y trouverez le langage doux et aggreable, d'une naïfve simplicité, la narration pure, et en laquelle la bonne foy de l'autheur reluit evidemment, exempte de vanité parlant de soy, et d'affection et d'envie parlant d'autruy : ses discours et enhortemens, accompaignez, plus de bon zele et de verité, que d'aucune exquise suffisance, et tout par tout de l'authorité et gravité, representant son homme de bon lieu, et élevé aux grans affaires.
Michel de Montaigne Essais Bk. II, ch. 10: "Des Livres"; translation from Serge Hughes (trans.) The Essential Montaigne (New York: New American Library, 1970) p. 293.
Criticism

As quoted in Sam Houston (2004), by James Haley, University of Oklahoma Press
1860s