“Calculations are to the economic science what bones are to the human body. Without them it will always be a vague and confused science, at the mercy of error and prejudice.”

"Proposed Automatic Calculating Machine" (1937)

Equality (1897)

Source: Testimony: its Posture in the Scientific World (1859), p. 10
Context: The fall of meteoric stones was occasionally reported by good witnesses during many ages. But science did not understand how stones should be formed in or beyond the atmosphere... The accounts of the fall of meteoric stones were held to be incompatible with the laws of nature, and specimens which had been seen to fall by hundreds of people were preserved in cabinets of natural history as ordinary minerals, 'which the credulous and superstitious regarded as having fallen from the clouds.' A committee of the French Academy of Sciences, including the celebrated Lavoisier, unanimously rejected an account of three nearly contemporary descents of meteorites which reached them on the strongest evidence. After two thousand years of incredulity, the truth in this matter was forced upon the scientific world about the beginning of the present century. There would have been at any time, of course, an instant cessation of skepticism if any one could have shewn, a priori, from ascertained principles in connection with the atmosphere, how stones were to be expected to fall from the sky. But what is this but to say that facts by themselves, however well attested, are wholly useless in such circumstances to the cultivators of physical science, while any kind of vague hypothesis can be brought forward in opposition to them? What is it but to put conjecture or prejudice above fact, and indeed utterly to repudiate the Baconian method?

Emancipation: A Romance of the Times to Come (1971)

Source: The Dervish House (2010), Ch. 2, §8 (p. 72)

The Origins of Knowledge and Imagination (1978)

Letter to Henrietta Jevons (28 February 1858), published in Letters and Journal of W. Stanley Jevons (1886), edited by Harriet A. Jevons, his wife, p. 101.
Context: You will perceive that economy, scientifically speaking, is a very contracted science; it is in fact a sort of vague mathematics which calculates the causes and effects of man's industry, and shows how it may be best applied. There are a multitude of allied branches of knowledge connected with mans condition; the relation of these to political economy is analogous to the connexion of mechanics, astronomy, optics, sound, heat, and every other branch more or less of physical science, with pure mathematics.

Postscript of letter to Mandell Creighton (5 April 1887), puplished in Historical Essays and Studies, by John Emerich Edward Dalberg-Acton (1907), edited by John Neville Figgis and Reginald Vere Laurence, Appendix, p. 505 http://oll.libertyfund.org/?option=com_staticxt&staticfile=show.php%3Ftitle=2201&chapter=203934&layout=html&Itemid=27
Context: ADVICE TO PERSONS ABOUT TO WRITE HISTORY — DON’T
In the Moral Sciences Prejudice is Dishonesty.
A Historian has to fight against temptations special to his mode of life, temptations from Country, Class, Church, College, Party, Authority of talents, solicitation of friends.
The most respectable of these influences are the most dangerous.
The historian who neglects to root them out is exactly like a juror who votes according to his personal likes or dislikes.
In judging men and things Ethics go before Dogma, Politics or Nationality. The Ethics of History cannot be denominational.
Judge not according to the orthodox standard of a system religious, philosophical, political, but according as things promote, or fail to promote the delicacy, integrity, and authority of Conscience.
Put conscience above both system and success.
History provides neither compensation for suffering nor penalties for wrong.

Part 1, Chapter 1, The Economy and Economics, p. 23
Economics For Everyone (2008)