
this harmonic proportion may be expressed as <math>\frac{12}{6}=\frac{12-8}{8-6}</math> or inversely.
Nicomachus of Gerasa: Introduction to Arithmetic (1926)
Nicomachus gives another reason for the name, viz. that a cube being of 3 equal dimensions, was the pattern άρμονία: and having 12 edges, 8 corners, 6 faces, it gave its name to harmonic proportion, since:<center>12:6 :: 12-8:8-6</center>
Footnote, citing Vide Cantor, Vorles [Vorlesüngen über Geschichte der Mathematik ?] p 152. Nesselmann p. 214 n. Hankel. p. 105 sqq.
A Short History of Greek Mathematics (1884)
this harmonic proportion may be expressed as <math>\frac{12}{6}=\frac{12-8}{8-6}</math> or inversely.
Nicomachus of Gerasa: Introduction to Arithmetic (1926)
[Denyer, Ralph, The Guitar Handbook, 2002, 114, 0-679-74275-1]
Elsewhere
From Frédéric Louis Ritter's French Tr. Introduction à l'art Analytique (1868) utilizing Google translate with reference to English translation in Jacob Klein, Greek Mathematical Thought and the Origin of Algebra (1968) Appendix
In artem analyticem Isagoge (1591)
“A wise man, therefore, proportions his belief to the evidence.”
Section X: Of Miracles; Part I. 87
An Enquiry Concerning Human Understanding (1748)
Context: In our reasonings concerning matter of fact, there are all imaginable degrees of assurance, from the highest certainty to the lowest species of moral evidence. A wise man, therefore, proportions his belief to the evidence.
Source: (1776), Book V, Chapter II, Part II, p. 892.
Draft for a Statement of Human Obligation (1943)
Context: The proportions of good and evil in any society depend partly upon the proportion of consent to that of refusal and partly upon the distribution of power between those who consent and those who refuse.
If any power of any kind is in the hands of a man who has not given total, sincere, and enlightened consent to this obligation such power is misplaced.
If a man has willfully refused to consent, then it is in itself a criminal activity for him to exercise any function, major or minor, public or private, which gives him control over people's lives. All those who, with knowledge of his mind, have acquiesced in his exercise of the function are accessories to the crime.
Any State whose whole official doctrine constitutes an incitement to this crime is itself wholly criminal. It can retain no trace of legitimacy.
Any State whose official doctrine is not primarily directed against this crime in all its forms is lacking in full legitimacy.
Any legal system which contains no provisions against this crime is without the essence of legality. Any legal system which provides against some forms of this crime but not others is without the full character of legality.
Any government whose members commit this crime, or authorize it in their subordinates, has betrayed its function.
Small Houses: Their Economic Design and Construction (1922)
“Every man is rich or poor according to the proportion between his desires and his enjoyments”
No. 163 (8 October 1751)
The Rambler (1750–1752)
Context: Every man is rich or poor according to the proportion between his desires and his enjoyments; any enlargement of wishes is therefore equally destructive to happiness with the diminution of possession, and he that teaches another to long for what he never shall obtain is no less an enemy to his quiet than if he had robbed him of part of his patrimony.