Guns, Germs, and Steel

by Jared Diamond

  One reason why technology tends to catalyze itself is that advances depend upon previous mastery of simpler problems. For example, Stone Age farmers did not proceed directly to extracting and working iron, which requires high-temperature furnaces. Instead, iron ore metallurgy grew out of thousands of years of human experience with natural outcrops of pure metals soft enough to be hammered into shape without heat (copper and gold). It also grew out of thousands of years of development of simple furnaces to make pottery, and then to extract copper ores and work copper alloys (bronzes) that do not require as high temperatures as does iron. In both the Fertile Crescent and China, iron objects became common only after about 2,000 years of experience of bronze metallurgy. New World societies had just begun making bronze artifacts and had not yet started making iron ones at the time when the arrival of Europeans truncated the New World’s independent trajectory.

  The other main reason for autocatalysis is that new technologies and materials make it possible to generate still other new technologies by recombination. For instance, why did printing spread explosively in medieval Europe after Gutenberg printed his Bible in A.D. 1455, but not after that unknown printer printed the Phaistos disk in 1700 B.C.? The explanation is partly that medieval European printers were able to combine six technological advances, most of which were unavailable to the maker of the Phaistos disk. Of those advances—in paper, movable type, metallurgy, presses, inks, and scripts—paper and the idea of movable type reached Europe from China. Gutenberg’s development of typecasting from metal dies, to overcome the potentially fatal problem of nonuniform type size, depended on many metallurgical developments: steel for letter punches, brass or bronze alloys (later replaced by steel) for dies, lead for molds, and a tin-zinc-lead alloy for type. Gutenberg’s press was derived from screw presses in use for making wine and olive oil, while his ink was an oil-based improvement on existing inks. The alphabetic scripts that medieval Europe inherited from three millennia of alphabet development lent themselves to printing with movable type, because only a few dozen letter forms had to be cast, as opposed to the thousands of signs required for Chinese writing.

  In all six respects, the maker of the Phaistos disk had access to much less powerful technologies to combine into a printing system than did Gutenberg. The disk’s writing medium was clay, which is much bulkier and heavier than paper. The metallurgical skills, inks, and presses of 1700 B.C. Crete were more primitive than those of A.D. 1455 Germany, so the disk had to be punched by hand rather than by cast movable type locked into a metal frame, inked, and pressed. The disk’s script was a syllabary with more signs, of more complex form, than the Roman alphabet used by Gutenberg. As a result, the Phaistos disk’s printing technology was much clumsier, and offered fewer advantages over writing by hand, than Gutenberg’s printing press. In addition to all those technological drawbacks, the Phaistos disk was printed at a time when knowledge of writing was confined to a few palace or temple scribes. Hence there was little demand for the disk maker’s beautiful product, and little incentive to invest in making the dozens of hand punches required. In contrast, the potential mass market for printing in medieval Europe induced numerous investors to lend money to Gutenberg.

  HUMAN TECHNOLOGY DEVELOPED from the first stone tools, in use by two and a half million years ago, to the 1996 laser printer that replaced my already outdated 1992 laser printer and that was used to print this book’s manuscript. The rate of development was undetectably slow at the beginning, when hundreds of thousands of years passed with no discernible change in our stone tools and with no surviving evidence for artifacts made of other materials. Today, technology advances so rapidly that it is reported in the daily newspaper.

  In this long history of accelerating development, one can single out two especially significant jumps. The first, occurring between 100,000 and 50,000 years ago, probably was made possible by genetic changes in our bodies: namely, by evolution of the modern anatomy permitting modern speech or modern brain function, or both. That jump led to bone tools, single-purpose stone tools, and compound tools. The second jump resulted from our adoption of a sedentary lifestyle, which happened at different times in different parts of the world, as early as 13,000 years ago in some areas and not even today in others. For the most part, that adoption was linked to our adoption of food production, which required us to remain close to our crops, orchards, and stored food surpluses.

  Sedentary living was decisive for the history of technology, because it enabled people to accumulate nonportable possessions. Nomadic hunter-gatherers are limited to technology that can be carried. If you move often and lack vehicles or draft animals, you confine your possessions to babies, weapons, and a bare minimum of other absolute necessities small enough to carry. You can’t be burdened with pottery and printing presses as you shift camp. That practical difficulty probably explains the tantalizingly early appearance of some technologies, followed by a long delay in their further development. For example, the earliest attested precursors of ceramics are fired clay figurines made in the area of modern Czechoslovakia 27,000 years ago, long before the oldest known fired clay vessels (from Japan 14,000 years ago). The same area of Czechoslovakia at the same time has yielded the earliest evidence for weaving, otherwise not attested until the oldest known basket appears around 13,000 years ago and the oldest known woven cloth around 9,000 years ago. Despite these very early first steps, neither pottery nor weaving took off until people became sedentary and thereby escaped the problem of transporting pots and looms.

  Besides permitting sedentary living and hence the accumulation of possessions, food production was decisive in the history of technology for another reason. It became possible, for the first time in human evolution, to develop economically specialized societies consisting of non-food-producing specialists fed by food-producing peasants. But we already saw, in Part 2 of this book, that food production arose at different times in different continents. In addition, as we’ve seen in this chapter, local technology depends, for both its origin and its maintenance, not only on local invention but also on the diffusion of technology from elsewhere. That consideration tended to cause technology to develop most rapidly on continents with few geographic and ecological barriers to diffusion, either within that continent or on other continents. Finally, each society on a continent represents one more opportunity to invent and adopt a technology, because societies vary greatly in their innovativeness for many separate reasons. Hence, all other things being equal, technology develops fastest in large productive regions with large human populations, many potential inventors, and many competing societies.

  Let us now summarize how variations in these three factors—time of onset of food production, barriers to diffusion, and human population size—led straightforwardly to the observed intercontinental differences in the development of technology. Eurasia (effectively including North Africa) is the world’s largest landmass, encompassing the largest number of competing societies. It was also the landmass with the two centers where food production began the earliest: the Fertile Crescent and China. Its east-west major axis permitted many inventions adopted in one part of Eurasia to spread relatively rapidly to societies at similar latitudes and climates elsewhere in Eurasia. Its breadth along its minor axis (north-south) contrasts with the Americas’ narrowness at the Isthmus of Panama. It lacks the severe ecological barriers transecting the major axes of the Americas and Africa. Thus, geographic and ecological barriers to diffusion of technology were less severe in Eurasia than in other continents. Thanks to all these factors, Eurasia was the continent on which technology started its post-Pleistocene acceleration earliest and resulted in the greatest local accumulation of technologies.

  North and South America are conventionally regarded as separate continents, but they have been connected for several million years, pose similar historical problems, and may be considered together for comparison with Eurasia. The Americas form the world’s second-largest landmass, significantly smaller than Eura
sia. However, they are fragmented by geography and by ecology: the Isthmus of Panama, only 40 miles wide, virtually transects the Americas geographically, as do the isthmus’s Darien rain forests and the northern Mexican desert ecologically. The latter desert separated advanced human societies of Mesoamerica from those of North America, while the isthmus separated advanced societies of Mesoamerica from those of the Andes and Amazonia. In addition, the main axis of the Americas is north-south, forcing most diffusion to go against a gradient of latitude (and climate) rather than to operate within the same latitude. For example, wheels were invented in Mesoamerica, and llamas were domesticated in the central Andes by 3000 B.C., but 5,000 years later the Americas’ sole beast of burden and sole wheels had still not encountered each other, even though the distance separating Mesoamerica’s Maya societies from the northern border of the Inca Empire (1,200 miles) was far less than the 6,000 miles separating wheel- and horse-sharing France and China. Those factors seem to me to account for the Americas’ technological lag behind Eurasia.

  Sub-Saharan Africa is the world’s third largest landmass, considerably smaller than the Americas. Throughout most of human history it was far more accessible to Eurasia than were the Americas, but the Saharan desert is still a major ecological barrier separating sub-Saharan Africa from Eurasia plus North Africa. Africa’s north-south axis posed a further obstacle to the diffusion of technology, both between Eurasia and sub-Saharan Africa and within the sub-Saharan region itself. As an illustration of the latter obstacle, pottery and iron metallurgy arose in or reached sub-Saharan Africa’s Sahel zone (north of the equator) at least as early as they reached western Europe. However, pottery did not reach the southern tip of Africa until around A.D. 1, and metallurgy had not yet diffused overland to the southern tip by the time that it arrived there from Europe on ships.

  Finally, Australia is the smallest continent. The very low rainfall and productivity of most of Australia makes it effectively even smaller as regards its capacity to support human populations. It is also the most isolated continent. In addition, food production never arose indigenously in Australia. Those factors combined to leave Australia the sole continent still without metal artifacts in modern times.

  Table 13.1 translates these factors into numbers, by comparing the continents with respect to their areas and their modern human populations. The continents’ populations 10,000 years ago, just before the rise of food production, are not known but surely stood in the same sequence, since many of the areas producing the most food today would also have been productive areas for hunter-gatherers 10,000 years ago. The differences in population are glaring: Eurasia’s (including North Africa’s) is nearly 6 times that of the Americas, nearly 8 times that of Africa’s, and 230 times that of Australia’s. Larger populations mean more inventors and more competing societies. Table 13.1 by itself goes a long way toward explaining the origins of guns and steel in Eurasia.

  TABLE 13.1 Human Populations of the Continents

  Continent

  1990 Population

  Area (square miles)

  Eurasia and North Africa

  4,120,000,000

  24,200,000

  (Eurasia)

  (4,000,000,000)

  (21,500,000)

  (North Africa)

  (120,000,000)

  (2,700,000)

  North America and South America

  736,000,000

  16,400,000

  Sub-Saharan Africa

  535,000,000

  9,100,000

  Australia

  18,000,000

  3,000,000

  All these effects that continental differences in area, population, ease of diffusion, and onset of food production exerted on the rise of technology became exaggerated, because technology catalyzes itself. Eurasia’s considerable initial advantage thereby was translated into a huge lead as of A.D. 1492—for reasons of Eurasia’s distinctive geography rather than of distinctive human intellect. The New Guineans whom I know include potential Edisons. But they directed their ingenuity toward technological problems appropriate to their situations: the problems of surviving without any imported items in the New Guinea jungle, rather than the problem of inventing phonographs.

  CHAPTER 14

  FROM EGALITARIANISM TO KLEPTOCRACY

  IN 1979, WHILE I WAS FLYING WITH MISSIONARY FRIENDS over a remote swamp-filled basin of New Guinea, I noticed a few huts many miles apart. The pilot explained to me that, somewhere in that muddy expanse below us, a group of Indonesian crocodile hunters had recently come across a group of New Guinea nomads. Both groups had panicked, and the encounter had ended with the Indonesians shooting several of the nomads.

  My missionary friends guessed that the nomads belonged to an uncontacted group called the Fayu, known to the outside world only through accounts by their terrified neighbors, a missionized group of erstwhile nomads called the Kirikiri. First contacts between outsiders and New Guinea groups are always potentially dangerous, but this beginning was especially inauspicious. Nevertheless, my friend Doug flew in by helicopter to try to establish friendly relations with the Fayu. He returned, alive but shaken, to tell a remarkable story.

  It turned out that the Fayu normally lived as single families, scattered through the swamp and coming together once or twice each year to negotiate exchanges of brides. Doug’s visit coincided with such a gathering, of a few dozen Fayu. To us, a few dozen people constitute a small, ordinary gathering, but to the Fayu it was a rare, frightening event. Murderers suddenly found themselves face-to-face with their victim’s relatives. For example, one Fayu man spotted the man who had killed his father. The son raised his ax and rushed at the murderer but was wrestled to the ground by friends; then the murderer came at the prostrate son with an ax and was also wrestled down. Both men were held, screaming in rage, until they seemed sufficiently exhausted to be released. Other men periodically shouted insults at each other, shook with anger and frustration, and pounded the ground with their axes. That tension continued for the several days of the gathering, while Doug prayed that the visit would not end in violence.

  The Fayu consist of about 400 hunter-gatherers, divided into four clans and wandering over a few hundred square miles. According to their own account, they had formerly numbered about 2,000, but their population had been greatly reduced as a result of Fayu killing Fayu. They lacked political and social mechanisms, which we take for granted, to achieve peaceful resolution of serious disputes. Eventually, as a result of Doug’s visit, one group of Fayu invited a courageous husband-and-wife missionary couple to live with them. The couple has now resided there for a dozen years and gradually persuaded the Fayu to renounce violence. The Fayu are thereby being brought into the modern world, where they face an uncertain future.

  Many other previously uncontacted groups of New Guineans and Amazonian Indians have similarly owed to missionaries their incorporation into modern society. After the missionaries come teachers and doctors, bureaucrats and soldiers. The spreads of government and of religion have thus been linked to each other throughout recorded history, whether the spread has been peaceful (as eventually with the Fayu) or by force. In the latter case it is often government that organizes the conquest, and religion that justifies it. While nomads and tribespeople occasionally defeat organized governments and religions, the trend over the past 13,000 years has been for the nomads and tribespeople to lose.

  At the end of the last Ice Age, much of the world’s population lived in societies similar to that of the Fayu today, and no people then lived in a much more complex society. As recently as A.D. 1500, less than 20 percent of the world’s land area was marked off by boundaries into states run by bureaucrats and governed by laws. Today, all land except Antarctica’s is so divided. Descendants of those societies that achieved centralized government and organized religion earliest ended up dominating the modern world. The combination of government and religion has thus functioned, together with germs, writing, and technology, as one of th
e four main sets of proximate agents leading to history’s broadest pattern. How did government and religion arise?

  FAYU BANDS AND modern states represent opposite extremes along the spectrum of human societies. Modern American society and the Fayu differ in the presence or absence of a professional police force, cities, money, distinctions between rich and poor, and many other political, economic, and social institutions. Did all of those institutions arise together, or did some arise before others? We can infer the answer to this question by comparing modern societies at different levels of organization, by examining written accounts or archaeological evidence about past societies, and by observing how a society’s institutions change over time.

  Cultural anthropologists attempting to describe the diversity of human societies often divide them into as many as half a dozen categories. Any such attempt to define stages of any evolutionary or developmental continuum—whether of musical styles, human life stages, or human societies—is doubly doomed to imperfection. First, because each stage grows out of some previous stage, the lines of demarcation are inevitably arbitrary. (For example, is a 19-year-old person an adolescent or a young adult?) Second, developmental sequences are not invariant, so examples pigeonholed under the same stage are inevitably heterogeneous. (Brahms and Liszt would turn in their graves to know that they are now grouped together as composers of the romantic period.) Nevertheless, arbitrarily delineated stages provide a useful shorthand for discussing the diversity of music and of human societies, provided one bears in mind the above caveats. In that spirit, we shall use a simple classification based on just four categories—band, tribe, chiefdom, and state (see Table 14.1)—to understand societies.