Political economists and arithmeticians admitted, however, that human behavior was not quite as predictable as the recurring patterns in the material world. But human bodies were themselves material. So political arithmeticians started with those bodies, the natural entities on which they built a science. To make their claims credible, however, these early theorists made a distinction between facts and probabilities.
The distinction existed in natural science as well. Different philosophers had different views as to whether facts outweighed probabilities or the reverse, but most agreed that the distinction was worth making. A fact was something that people could agree was certain or nearly so; a probability was something that people agreed was likely. Something probable was not a fact, yet it was not mere opinion. For example, a political arithmetician might state that data, such as the annual number of deaths in a city, were facts. But an estimate of how many people might die the next year was a probability. (A belief that God had struck down sinners while sparing the righteous was an opinion.) A probability was a kind of guess, a way to make a decision in the face of uncertainty. Any such decision was, in a way, a gamble.22
Indeed, Franklin’s contemporaries referred to insurance, one aspect of political arithmetic, as a business that bet on lives. Someone who sold insurance, whether on a life or a piece of property, was gambling that he or she had correctly estimated the probability that payments for insurance would be greater than the cost of paying any claims. Conversely, whoever bought insurance was betting that the payment of premiums was worthwhile, given the estimated likelihood of personal disaster.23
Franklin had made his first foray into these questions of probability in 1722. That year, he used Silence Dogood to argue for “An Office of Ensurance for Widows.” This proposal estimated death and survival rates based on the population dynamics for “Two thousand Women” and their husbands. The scheme would pay premiums tied to the amount each household had paid in and to the age of the widow’s husband at his death. In support of this, the Widow Dogood rather learnedly cited “Sir William Petty in his Political Arithmetick.”24
Petty came in handy again, seven years later, when Franklin recommended a paper currency for Pennsylvania. The colony had been trying to make do with an array of coins and currency from other places or with awkward forms of credit. But Franklin thought this was too limited and inconvenient a system to encourage economic growth. His Modest Enquiry into the Nature and Necessity of a Paper-Currency (1729) used Petty’s Treatise of Taxes and Contributions (1662) to plead for a currency. Franklin’s main argument was that “the Riches of a Country are to be valued by the Quantity of Labour its Inhabitants are able to purchase.” A currency for Pennsylvania would, he argued, encourage the immigration of the “Labouring and Handicrafts Men” whose work was most valuable. The currency would also “occasion a much greater Vent and Demand for [British] Commodities here.” Immigration, production, and consumption would all increase. It took a former workingman to define a rudimentary form of the labor theory of value.25
The pamphlet on this topic marked the first time that Franklin used circulation to explain something about human society. If financial transactions were easier, he said, “money which otherwise would have lain dead in [bankers’] Hands, is made to circulate again.” It was paper bills that would in fact accelerate the movement of capital, commodities, and labor because they were “lighter in Carriage, concealed in less Room, and therefore safer in Travelling or Laying up.” Members of the Pennsylvania Assembly were so taken with the idea that they hired Franklin to print the currency he advocated. It was “a very profitable Jobb,” he congratulated himself.26
Thereafter, claims about population growth, economic value, and costs and benefits became hallmarks of Franklin’s writings. This was true of one of his famous civic improvements, Philadelphia’s Union Fire Company, which was essentially an insurance organization. Franklin had helped create it in 1736 for “the better preserving our Goods and Effects from Fire.” Its members were bound in “Friendship” to maintain buckets and cloth bags, the former to douse fires and the latter to rescue portable goods. They promised to use this equipment to protect each other’s property. Widows would inherit their husbands’ status in the company. All this spread out the cost of fighting urban fires, a considerable hazard, much as insurance payments spread out the cost of reimbursement for other human tragedies.27
Political arithmetic and economy also made Franklin doubt the value of imported labor, especially slaves. Numbers were his proof. In 1731, he had analyzed the city’s smallpox deaths in the Pennsylvania Gazette. Franklin reported that the total number of dead was “exactly 288, and no more.” Sixty-four who died “were Negroes,” meaning slaves. If slaves’ average individual value was £30, the total loss was nearly £2,000. In his calculation, Franklin disapprovingly notified the public of the enormous expense that slaves represented. One year later, in 1732, the Junto asked if “the Importation of Servants [would] increase or advance the Wealth of our Country?”28
Clearly, Franklin and others in Philadelphia were concluding that their colony might become a destination so attractive that productive people would migrate there freely. By fostering the circulation of people to the colony, the circulation of paper currency would help to make the colony an economic success. Settled residents would then have no need to pay to import any workers, including slaves. All of this assumed, however, that a body was a body was a body—that humans were fairly interchangeable in their composition and therefore their capacity to work, to migrate, and to produce wealth.
Were they? Here, Franklin ran up against the crucial question that Thomas Tryon had raised: Were all humans alike? It had been traditional to think so. Christians were supposed to accept the scriptural admonition that humanity shared “one blood” and that each human had a soul equally subject to God. And in older theories of nature, the body was deemed a microcosm of the whole creation—each body had the same underlying composition. True, bodies seemed different, but only superficially. Different climates, it was thought, created differences in human bodies; Africans adapted to a burning sun and Europeans to cooler places. These characteristics did not weaken their underlying similarity because all were parts of God’s Creation. As one seventeenth-century English commentator hoped, the “black Negro” and “olive-colored American” Indian would “with the whiter European become one sheepe-fold, under one great shepheard.”29
But the newly precise ideas about bodies (about their hearts and blood, for instance) questioned whether humans had this cosmic connection with one another. Did the animal economy and the red circulating juice prove that all people were “cousins”? Or did some bodies digest food and pump blood differently?
Europeans tended to see differences, not similarities. The science of political arithmetic had turned humans into bodies to be studied, as if they were so many material objects, such as rocks or shrubs, that happened to have souls. Thus, William Petty speculated that human bodies were quite different. He compared Europeans and Africans, who differed not only in skin color but also “in the very outline of their faces and the Mould of their skulls.” The same was true, Petty ominously asserted, of “the internall Qualities of their Minds.” Another, anonymous seventeenth-century account, of the West Indies, assumed that Africans were “a people strong and able” to do heavy work in hot climates. As these emerging ideas of race were making clear, discussions about nature did not merely present facts. They made arguments—and sometimes troubling ones.30
Franklin never made up his mind about human difference. In Poor Richard for 1745, he declared, much as Tryon had done, that “All blood is alike ancient.” That was his generous side. In other cases, Franklin concluded that different people might have different bodily characteristics. Why had smallpox devastated American Indians? Franklin cited the testimony of Charles-Marie de La Condamine, a French natural philosopher who had traveled to Peru and who became an advocate of inoculation—a contemporary dubbed him th
e “Don Quixote of inoculation.” La Condamine wrote that he saw Indians in Peru swept away by smallpox. Indians in North America had suffered a similar fate. Climate could not explain this, for North American and South American Indians lived in quite different climates. So Franklin blamed their bodies, specifically, “the Closeness and Hardness of their Skins.” Indians everywhere, he speculated, had less of the insensible perspiration Sanctorius had identified in European bodies. Inoculation was, he thought, all the more necessary for Indians.31
When Franklin discussed inoculation of whites, he presented data: so many people had been treated, and so many of them had died. He compared those figures to mortality rates among uninoculated people who got smallpox. His calculations implied the probability that it was safer to be inoculated than to wait to get smallpox the ordinary way. There was an element of uncertainty in Franklin’s analysis, but it was as nothing compared to his hypothesis that Indians and whites had differently constructed skins. That was his opinion, merely.
FRANKLIN’S interest in the human body—its constitution, its health, its productivity—appeared to greatest effect in his Account of the New Invented Pennsylvanian Fire-Places . . . (1744). The pamphlet addressed a subject that he would consider throughout his life: heat. He seemed to have begun working on this topic in late 1739 and early 1740, in other words, in winter, the perfect time to worry about keeping warm.
Franklin’s dread of pulmonary disorders might, in part, have spurred his interest in improving heating systems. He crammed his 1744 pamphlet on fireplaces with warnings that drafts in poorly heated rooms were deadly. It did people little good to huddle by a fire, he argued, if currents of cold air then buffeted them. “Many Colds are caught from this Cause only,” Franklin lectured, “it being safer to sit in the open Street; for then the Pores do all close together, and the Air does not strike so sharply against any particular part.” Franklin also cited an alarming Spanish proverb, “If the Wind blows on you thro’ a Hole, Make your Will, and take Care of your Soul.” (He had first used this aphorism in Poor Richard for 1736, the year after his recent attack of pleurisy.) Over and over, he stressed the power of a “Crevice” or “Hole” to create “Colds . . . Fevers, Pleurisies, &c.” He worried that women especially suffered from “Colds in the Heads,” though interestingly, he did not assume an innate difference between men and women but instead suggested that the disparity occurred because women “sit much in the House” with its cold-producing drafts.32
Surely, houses and their occupants could be heated better. Franklin used the human body and its well-being—the “Comfort and Conveniency of our Lives”—as important measures of a successful heating system. He recognized that this was a new goal: “I suppose our Ancestors never thought of warming Rooms to sit in; all they purpos’d was to have a Place to make a Fire in.”33
Franklin’s “Pennsylvanian” fireplace was meant to warm a whole room, not just the space immediately around it. It could accomplish this because its interior, curving passage used convection. It would convey heat into the room and suck the smoke out. As it emitted heat, lighter air would rise “by the Mantle-piece to the Cieling and [spread] all over the Top of the Room,” then sink as more warmed air flowed from the fireplace until “the whole Room [became] in a short time equally warmed.” A cold draft within the fireplace pushed the smoke down the back of the chimney and through an “inverted siphon,” allowing the heat to flow forward and then outward to the room. Franklin stressed the naturalism of his design by placing, on the front plate of his fireplace, a small sun with the caption “ALTER IDEM,” meaning the fireplace was “another one,” another sun.34
Profile of Franklin’s fireplace. Benjamin Franklin, Account of the New Invented Pennsylvanian Fire-Places (1744). LIBRARY COMPANY OF PHILADELPHIA.
A properly heated room, like a properly maintained body, encouraged productivity, he asserted. In a room with an ordinary fireplace, people had to crowd around the fire. By its dim, flickering light, they squinted at their reading or ran sewing needles into their fingers. But a room with Franklin’s fireplace was fully heated. People could read or work in the light from windows. Unlike a closed stove, Franklin’s design allowed people to see the “pleasant” sight of the fire and to have access to it so they could “boil the Tea-kettle, warm the Flat-Irons, heat [portable] Heaters, keep warm a Dish of Victuals by setting it on the Top, &c. &c. &c”—an infinity of domestic comforts.35
Franklin’s fireplace—Guide to assembly. Benjamin Franklin, Account of the New Invented Pennsylvanian Fire-Places (1744). LIBRARY COMPANY OF PHILADELPHIA.
Franklin clearly knew the appeal of this domestic environment—a place of warmth, conviviality, and occupation. In this space, reading and housework might coexist, along with the male and female household members who did the reading and the work and enjoyed the comfort. Was this Franklin’s own idea of domestic bliss? It is hard to tell. Consider that Poor Richard had offered, in the same almanac, two maxims on domestic and physical warmth. One was sentimental: “A house without woman and Firelight, is like a body without soul or sprite”; the other was misogynist: “Ne’er take a wife till thou hast a house (and a fire) to put her in.”36
His vision of home and hearth was, above all, practical. Franklin used political economy and political arithmetic to promote his fire-places, which consumed much less fuel than ordinary fires. “As the Country is more clear’d and settled” in America, he predicted, wood “will of course grow scarcer and dearer.” Franklin’s fireplaces used so much less fuel that America’s wood could grow as fast as the expanding population could “consume it,” which would prevent the development of an expensive internal market for wood or a ruinous traffic in coal brought “over the Atlantick.” “We leave it to the Political Arithmetician,” Franklin wrote, “to compute, how much Money will be sav’d to a Country, by its spending two thirds less of Fuel.” There would also be concomitant savings in labor that could be shifted from cutting wood to cultivating land.37
How quintessentially Franklin the fireplace was. He had invented something! Moreover, the invention was practical: it made people more productive, and it was itself efficient—it embodied all the classic Franklin virtues. But this was a highly learned invention, whose description and directions for assembly and use came with footnotes, including footnotes in Latin. Those details were not strictly necessary. Why did Franklin bother to provide them?
In fact, the Pennsylvania fireplace was Franklin’s first experiment, his first venture into natural philosophy. That philosophy explained the causes of things. With his fireplace, he was exploring the cause of motion in air—why did it move when heated?. To show that he had read and thought about this as a question within natural science, he cited in his pamphlet no fewer than six works of natural philosophy, several of which synopsized other sources; Franklin’s phrasing in places betrayed a knowledge of still other texts in natural philosophy. If we look more closely at the pamphlet, we can determine what Franklin was reading and see what he was doing with all that reading.38
The first thing he did was define an experimental space, one he would use again and again: an enclosed room. This approach was a remarkably thrifty way of doing an experiment. Franklin could not afford the kind of specialized research spaces that gentleman philosophers commanded, but he owned a house, fireplaces, and his own heat-seeking body. Moreover, he could safely assume that his readers had access to rooms with fireplaces—and drafts—and thus could verify his findings if they wished.
He presupposed his experimental space to be full of air, a substance that would, when warm, rise and expand. Heating a room meant creating enough warm air to expand throughout it, repelling the cold drafts that plagued rooms where the warmth was too localized. (The problem could be detected, he advised, “by holding a Candle to a Keyhole.”) An efficient fireplace would fill a room with heat because hot air expanded. Just the opposite happened when air cooled—it contracted. To verify this, anyone could make “very easy Experiments” wit
h a bottle. Heat the bottle, Franklin instructed, and invert it in water and then watch water rise in the bottle as its air “cools and contracts.”39
The “very easy Experiments” are a big clue that the pamphlet was more than a practical description of a fireplace. The bottle was a barometer, perhaps Franklin’s nod to Robert Boyle and his air pump, which had established that air had a “spring” (meaning pressure). That pressure was an important reason to examine heat: temperature caused air to expand and contract, giving evidence of its material construction. Franklin was in fact accepting the prevailing learned opinion that matter was composed of an accumulation of particles that existed everywhere, even inside Philadelphia houses.40
Several figures in the early modern sciences had revived the ancient Greek idea that matter was composed of corpuscles or particles. They thought that these particles were (unlike our modern atoms) elemental, having no constituent parts. Where we see submolecular materials connecting and changing character, they thought corpuscles simply clumped or collided. The shape of the particles was, however, a matter of debate, with René Descartes and Isaac Newton offering the most important interpretations.
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