Horace Walpole’s journal for Saturday, March 22 reads: “With Lady [Louisa Kerr] and Lord George [Lennox], Mr and Mrs Carr, Duke of Buccleuch, Mr Scot, and Mr Nicholson to the Foire St-Germain, and supped afterwards at Lord George’s.”
Did Walpole leave out Adam Smith? Or did Smith leave his pupils, Duke Henry [“Duke of Buccleuch”] and the duke’s younger brother Hew Campbell Scot [“Mr Scot”], under the care of Walpole to attend the Foire St-Germain? Either way, the fair of Saint-Germain (pictured below), along with the fairs of Saint-Laurent and Saint-Ovide, were the principal centers of popular entertainment in Paris throughout most of the eighteenth century. These fairs were originally begun in the Middle Ages by monks to accommodate pilgrims who were congregating on certain feast days to honor relics; the monks then rented stalls to merchants to sell food and wares and eventually permitted entertainers to perform. The Saint-Germain fair, however, was the oldest and most “fashionable” of the three major fairs.
The Saint-Germain fair ran from February 3 until Palm Sunday. In 1766, Palm Sunday fell on March 23, so Walpole and his party visited the fair on its next-to-last day. What did they see there? Historian Robert M. Isherwood (1981, p. 25, footnotes omitted) describes the Saint-Germain fair thus:
"It comprised two huge markets 130 steps long and 100 wide, covered by a magnificent timbered roof built in the sixteenth century at the instigation of the abbe of Saint-Germain. The composer Charles Favart called this roof 'one of the marvels of Paris.' Beneath it a series of nine unpaved streets, lined with boutiques, crisscrossed the fair. Established on the site of the old hotel of the kings of Navarre, the whole terrain was sunken, forming what one observer called 'a mere hole in the middle of the faubourg....' The ground, much lower than it is today, was in some places six to eight feet deeper than the surrounding land. Visitors complained about the narrow passageways that had to be crossed to gain access to the fair. The danger of being hit by carriages descending into what Louis-Sebastien Mercier called 'this narrow gorge' did not deter thousands of people from attending the fair every day."
Moreover, the fairs attracted people from all walks of life and all social orders. According to Isherwood (1981, p. 27, footnotes omitted), for example:
"Typically, the fairs were clogged with soldiers, beggars, guardsmen, prostitutes, clerks, lackeys, students, shopkeepers, porters, and petits-maîtres. Everyone mingled in a jangling din of shouts, insults, and banter amid a cacaphony of whistles, tambourines, flutes, and street cries. 'It was a continual ebb and flow of people who pushed each other from one side to the other,' wrote Charles Sorel. 'It seemed that that day had been chosen by all the people of low rank in Paris to come there. . . One heard those who suffered from the discomfort screaming from every direction, and in vain pregnant women imagined that they would be more spared than others; one could not have lightened their burden if one had wished to.' For Joachim Nemeitz, who wrote an instructional guide for visitors to Paris, everyone at Saint-Germain moved 'helter-skelter, masters with valets and lackeys, thieves with honest people. The most refined courtesans, the prettiest girls, the subtlest pickpockets are as if intertwined together. The whole fair teems with people from the beginning to the end.'"
If Adam Smith did visit the Saint-Germain fair and rub shoulders against this mix of humanity, he would have seen a wide variety of foods and merchants. In the words of Isherwood (1981, pp. 25-26, footnotes omitted):
“A sumptuous array of food products was sold at Saint-Germain including pastry, spiced breads, jams, waffles, fruit, candy, wine, liqueur, tisane, beer, and eau de vie. The merchants who had stalls in the fair, some from Paris but many from Amiens, Rheims, Beauvais, and other communities, included wigmakers, engravers, linen sellers, cask makers, coopers, druggists, cabinetmakers, and locksmiths. The seventeenth-century writer Charles Sorel declared that the fair 'was a place of joy and even debauchery where one must certainly sell merchandise which would serve intemperance and vanity.'”
Also, among the many popular forms of entertainment on display at these fairs were games of chance. According to Isherwood (1981, p. 26, footnote omitted), for example: “Although ordinances were issued repeatedly against it, gambling also provided merchants with a source of revenue. A few at Saint-Germain earned several hundred livres a day by running dice games, lotteries, spinning wheels, cards, and skittles in their boutiques.” Moreover, since the boutiques with gambling were usually packed with people, “they were favorite haunts of pickpockets who were adept at cutting off the backs of men’s coats or women’s dresses.”
Although Adam Smith does not mention any of the fairs of Paris by name in The Wealth of Nations, he does discuss the psychology of lotteries in Chapter 10 of Book 1 of his magnum opus, anticipating the work of Amos Tversky and Daniel Kahneman by three centuries:
"The over-weening conceit which the greater part of men have of their own abilities is an ancient evil remarked by the philosophers and moralists of all ages. Their absurd presumption in their own good fortune has been less taken notice of. It is, however, if possible, still more universal. There is no man living who, when in tolerable health and spirits, has not some share of it. The chance of gain is by every man more or less overvalued and the chance of loss is by most men undervalued, and by scarce any man, who is in tolerable health and spirits, valued more than it is worth. "That the chance of gain is naturally overvalued, we may learn from the universal success of lotteries. The world neither ever saw, nor ever will see, a perfectly fair lottery; or one in which the whole gain compensated the whole loss; because the undertaker could make nothing by it. In the state lotteries the tickets are really not worth the price which is paid by the original subscribers, and yet commonly sell in the market for twenty, thirty, and sometimes forty per cent advance. The vain hope of gaining some of the great prizes is the sole cause of this demand. The soberest people scarce look upon it as a folly to pay a small sum for the chance of gaining ten or twenty thousand pounds; though they know that even that small sum is perhaps twenty or thirty per cent more than the chance is worth. In a lottery in which no prize exceeded twenty pounds, though in other respects it approached much nearer to a perfectly fair one than the common state lotteries, there would not be the same demand for tickets. In order to have a better chance for some of the great prizes, some people purchase several tickets, and others, small share in a still greater number. There is not, however, a more certain proposition in mathematics than that the more tickets you adventure upon, the more likely you are to be a loser. Adventure upon all the tickets in the lottery, and you lose for certain; and the greater the number of your tickets the nearer you approach to this certainty."
In other words, if Adam Smith did visit the Saint-Germain fair, he probably did not partake of any of the games of chance being offered there. Either way, Saturday, March 22 would have been the last day of the Saint-Germain fair, as the next day was Palm Sunday. How did Adam Smith spend his Sundays in Paris, at the altar of God at one of the many chapels of the metropolis or at the altar of reason at the salon of the Baron d’Holbach?
 Lewis 1939, p. 309. Alas, I have been unable to determine who the Carrs were or who “Mr Nicholson” refers to. The names “Carr” and “Nicholson” do not appear anywhere else in Walpole’s travel journal or letters.
 Isherwood 1981, p. 24.
 Ibid., pp. 24-25.
 Ibid., p. 25.
 Isherwood 1981, p. 25, quoting Dumolard 1808, p. 25, Lister 2011, p. 147, and Mercier 1882, p. 103.
 Isherwood 1981, p. 27, quoting Sorel 1648, pp. 464-465, and Neimitz 1727, p. 170. Isherwood adds (1981, p. 30, footnotes omitted):
The [primary] sources stress the mixed social composition of fair audiences and crowds. In his tourist guide Le Voyageur fidèle (1716) Louis Liger spoke of “a great concourse of people from every social rank” at the Saint- German fair, and Germain Brice noted that the fair attracted “people of all kinds.” Later in the century, the Mémoires secrets noted that the low cost of tickets at the popular theaters enabled everyone to go, “so that the duchess and the savoyard rub shoulders there without distinction.” Jean-Baptiste Nougaret emphasized that the fair attracted artisans as well as the “dregs of the population,” and Rétif de la Bretonne observed that a crowd watching a parade at the fair included workers, scrubbing women, gauze-makers, seamstresses, pickpockets, and prostitutes, but also uncorrupted apprentices, children of good families, and artisans’ daughters.”
Isherwood 1981, p. 30, quoting Liger 1715, p. 244, Bachaumount in Lough 1957, p. 207, Nougaret 1777, p. 76, and Rétif de la Bretonne 1789, p. 40.
 Isherwood 1981, pp. 25-26, quoting Sorel 1648, p. 458.
 Isherwood 1981, p. 26, footnote omitted.
 Ibid., p. 26, footnote omitted. Isherwood further notes that the Secretaire d’Etat for Paris cracked down hard on games of chance in the late 1770s, “which some believe contributed to the decline of the fairs at the end of the century.” Ibid., footnote omitted.
 The Wealth of Nations, Glasgow edition, pp. 124-125 (paragraphs 26 & 27).