… is from page 534 of Book IV, Chapter 5  of the 1981 Liberty Fund edition  of Adam Smith’s 1776 An Inquiry Into the Nature and Causes of the Wealth of Nations :
I have no great faith in political arithmetick….
DBx: Smith chose his words with extraordinary care and exactness. When Smith said that he has no great faith in statistics – which in his day were called “political arithmetic” – he expressed his wise understanding that data do not speak for themselves (as so many unwise people wrongly suppose them to speak). And therefore, for statistics to contribute to our knowledge requires the critical judgment of those who use them. Statistics are not to be taken at face value with a tender faith that they convey correct understanding independently of either the user’s critical faculties and of the theory that the user brings to his or her interpretation of reality.
The first meeting of my Smithian Seminar II will occur this evening on George Mason’s Fairfax campus. Seventeen GMU students and I (along with philosopher Danny Shapiro, who is visiting GMU this year from West Virginia University ) will read the Wealth of Nations cover to cover (save for the “Digression on Silver) and discuss the text critically and open-mindedly. (Many of the students have taken my colleague Dan Klein’s Smithian Seminar I, but that class is not a prerequisite for the one that I teach.)
Although I enjoy and cherish the Wealth of Nations throughout, my favorite part is Book IV, in which Smith investigates mercantilist doctrines. I’m sure that every one of my students will recognize – with a mixture of amazement, bewilderment, and sadness – that the mercantilist dogmas and pronouncements that Smith in 1776 exposed as being utterly (and in some cases comically) fallacious are still prominent today, identical in all essentials to those of 241 years ago.
We economists have done a poor job of opening the eyes of the general public to the errors and dangers of mercantilism.