“This observation is merely the extension of a law”
Introductory
A Treatise on Man and the Development of His Faculties (1842)
Context: This observation is merely the extension of a law well known to all who have studied the condition of society in a philosophic manner: it is, that so long as the same causes exist, we must expect a repetition of the same effects. What has induced some to believe that moral phenomena did not obey this law, has been the too great influence ascribed all times to man himself over his actions.
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Adolphe Quetelet 52
Belgian astronomer, mathematician, statistician and sociolo… 1796–1874Related quotes

“Let observation with extensive view
Survey mankind, from China to Peru.”
Source: Vanity of Human Wishes (1749), Line 1; comparable to: "All human race, from China to Peru, Pleasure, howe’er disguis’d by art, pursue", Thomas Warton, Universal Love of Pleasure

“Do you decide to observe? Or do you merely observe?”
5th Public Talk Saanen (26th July 1970); also in "Fear and Pleasure", The Collected Works, Vol. X
1970s
Context: Do you decide to observe? Or do you merely observe? Do you decide and say, "I am going to observe and learn"? For then there is the question: "Who is deciding?" Is it will that says, "I must"? And when it fails, it chastises itself further and says, "I must, must, must"; in that there is conflict; therefore the state of mind that has decided to observe is not observation at all. You are walking down the road, somebody passes you by, you observe and you may say to yourself, "How ugly he is; how he smells; I wish he would not do this or that". You are aware of your responses to that passer-by, you are aware that you are judging, condemning or justifying; you are observing. You do not say, "I must not judge, I must not justify". In being aware of your responses, there is no decision at all. You see somebody who insulted you yesterday. Immediately all your hackles are up, you become nervous or anxious, you begin to dislike; be aware of your dislike, be aware of all that, do not "decide" to be aware. Observe, and in that observation there is neither the "observer" nor the "observed" — there is only observation taking place. The "observer" exists only when you accumulate in the observation; when you say, "He is my friend because he has flattered me", or, "He is not my friend, because he has said something ugly about me, or something true which I do not like." That is accumulation through observation and that accumulation is the observer. When you observe without accumulation, then there is no judgement.

1990s and beyond, "The Agenbite of Outwit" (1998)

Source: The Production of Security (1849), p. 32

My Day (1935–1962)
Context: I was one of those who was very happy when the original prohibition amendment passed. I thought innocently that a law in this country would automatically be complied with, and my own observation led me to feel rather ardently that the less strong liquor anyone consumed the better it was. During prohibition I observed the law meticulously, but I came gradually to see that laws are only observed with the consent of the individuals concerned and a moral change still depends on the individual and not on the passage of any law. (14 July 1939)

Introductory
A Treatise on Man and the Development of His Faculties (1842)

Source: A Companion to Jan Hus (2015), p. 231.
J. R. Partington, Higher Mathematics for Chemical Students (1911)