Horizons

The Global Origins of Modern Science

James Poskett

• Publisher: Mariner Books
• Year: 2022
• ISBN:
  9780358265702
• Topic: History
• Subtopic: Science History
• Index: History

The history of science as it has never been told before: a tale of outsiders and unsung heroes from far beyond the Western canon that most of us are taught.

When we think about the origins of modern science we usually begin in Europe. We remember the great minds of Nicolaus Copernicus, Isaac Newton, Charles Darwin, and Albert Einstein. But the history of science is not, and has never been, a uniquely European endeavor. Copernicus relied on mathematical techniques that came from Arabic and Persian texts. Newton's laws of motion used astronomical observations made in Asia and Africa. When Darwin was writing On the Origin of Species, he consulted a sixteenth-century Chinese encyclopedia. And when Einstein studied quantum mechanics, he was inspired by the Bengali physicist, Satyendra Nath Bose.

Horizons is the history of science as it has never been told before, uncovering its unsung heroes and revealing that the most important scientific breakthroughs have come from the exchange of ideas from different cultures around the world. In this ambitious, revelatory history, James Poskett recasts the history of science, uncovering the vital contributions that scientists in Africa, America, Asia, and the Pacific have made to this global story.

Part One

Scientific Revolution, c. 1450–1700

1.New Worlds

Stepping out into the Mexican sun, Emperor Moctezuma II could hear the birds calling. His palace – located at the heart of the Aztec capital city of Tenochtitlan – housed an aviary, in which birds from all over the Americas were kept. Green parakeets perched on the latticework, whilst purple hummingbirds flashed through the trees. Alongside the aviary, Moctezuma’s palace featured a menagerie in which larger animals lived, including a jaguar and a coyote. But of all the wonders of nature, Moctezuma most appreciated flowers. Each morning, he would take a turn around the royal botanical garden. Roses and vanilla flowers lined the paths, whilst hundreds of Aztec gardeners tended to rows of medicinal plants.¹

Built in 1467, this Aztec botanical garden predated European examples by almost a century. And it wasn’t just for show. The Aztecs developed a sophisticated understanding of the natural world. They categorized plants according to their structure as well as use, particularly distinguishing between decorative and medicinal plants. Aztec scholars also reflected on the relationship between the natural world and the heavens, arguing – much like in the Christian tradition – that plants and animals were the handiwork of the gods. Moctezuma himself took great interest in all this. He commissioned surveys of the natural history of the Aztec Empire and made vast collections of animal skins and dried flowers. An accomplished scholar in his own right, Moctezuma is described in Aztec chronicles as ‘by nature wise, an astrologer, a philosopher, skilled in all the arts’. He stood at the head of a vast empire, one in which science reached new heights.²

Tenochtitlan was an engineering marvel. Built on an island at the centre of Lake Texcoco in 1325, the Aztec capital could only be reached by crossing one of three causeways, each stretching several miles across the water. Just like Venice, the city was criss-crossed by canals, with Aztec merchants paddling back and forth in canoes as they went about their daily business. An aqueduct provided the city with a supply of fresh water, whilst, out on the lake, farmers tended to strips of reclaimed land, growing maize, tomatoes, and chillies. At the centre of the city stood the Great Temple, an immense stone pyramid, over sixty metres tall. Aztec architects had designed the temple to align perfectly with the rising and setting of the Sun on key feast days. Moctezuma himself would attend ceremonies, praising the gods and offering tribute in the form of flowers, animal skins, and sometimes human sacrifice. By the middle of the fifteenth century, Tenochtitlan had grown to an unprecedented size. With a population of over 200,000, this Aztec megacity was much larger than most European capitals, including London and Rome. Over the following decades, the Aztec Empire continued to expand, stretching right across the Mexican plateau and incorporating over three million people.³

All this was made possible thanks to the advanced state of Aztec science and technology. From observing the heavens to studying the natural world, the Aztecs placed great emphasis on the cultivation of knowledge. Unlike most European kingdoms at the time, a significant proportion of Aztec children, both male and female, received some kind of formal education. There were also specialist schools for noble boys who wished to train as priests, a profession that required expert knowledge of astronomy and mathematics in order to compile the Aztec calendar. Alongside priests, there was a special class of people referred to as ‘knowers of things’. These were highly trained individuals, the equivalent of a university-educated scholar in Europe. They built up great libraries, often contributing new works themselves. The Aztecs also developed one of the most advanced medical systems in the world at that time. In Tenochtitlan, you could consult a range of medical practitioners, from physicians known as ticitl, to surgeons, midwives, and apothecaries. The city even housed a medical market, where traders from across the empire brought herbs, roots, and ointments for sale. Today we know that many Aztec medicinal plants do have pharmacologically active properties. These include a type of daisy that can be used to induce labour, as well as a species of Mexican marigold that helps reduce inflammation.⁴

Much of what we know about Tenochtitlan comes from accounts written by the people who destroyed it. On 8 November 1519, the Spanish conquistador Hernán Cortés entered the city for the first time. Initially, Moctezuma welcomed the Spanish, housing Cortés and his men in the royal palace. They were overwhelmed by what they saw. Bernal Díaz del Castillo, one of the soldiers who accompanied Cortés, later described Moctezuma’s gardens in The True History of the Conquest of New Spain (1576):

We went to the orchard and garden, which was such a wonderful thing to see and walk in, that I was never tired of looking at the diversity of the trees, and noting the scent which each one had, and the paths full of roses and flowers, and the many fruit trees and native roses, and the pond full of fresh water.

Díaz also described the aviary. He recalled seeing ‘everything from the royal eagle . . . down to tiny birds of many-coloured plumage . . . feathers of five colours – green, red, white, yellow and blue’. There was also a ‘great tank of fresh water and in it all other sorts of birds with long stilted legs, with body, wings, and tail all red’.⁵

The tranquillity did not last. Cortés took advantage of the situation, taking Moctezuma hostage and fighting his way through the city. And although the Spanish were initially repelled, Cortés returned with a far greater force two years later. Ships armed with cannon surrounded the city on the lake, as Spanish soldiers drove through the gates. Moctezuma was murdered and the Great Temple was destroyed. Cortés himself set fire to the palace. The aviary, the menagerie, and the gardens all burned. As Díaz noted, somewhat mournfully for a soldier, ‘of all these wonders that I then beheld . . . today all is overthrown and lost, nothing left standing’. The conquest of the Aztecs marked the beginning of the Spanish Empire in the Americas. In 1533, Charles V established the Viceroyalty of New Spain. The capital, Mexico City, was built on the ashes of Moctezuma’s palace.⁶

Most histories of science do not begin with the Aztecs in Mexico. Traditionally, the history of modern science begins in sixteenth-century Europe, with what is often called the ‘scientific revolution’. We are told that, in the period between around 1500 and 1700, an incredible transformation in scientific thought took place. In Italy, Galileo Galilei observed the moons of Jupiter, whilst in England, Robert Boyle first described the behaviour of gases. In France, René Descartes developed a new way of doing geometry, whilst in Holland, Antonie van Leeuwenhoek first observed bacteria under a microscope. Typically, this story culminates with the work of Isaac Newton, the great English mathematician who set out the laws of motion in 1687.⁷

Historians have long argued over the nature and causes of the scientific revolution. Some see this as a period of intellectual advance, one in which a few lone geniuses made new observations and challenged medieval superstition. Others argue that this was a period of great social and religious change, one in which the English Civil War and the Protestant Reformation forced people to reassess a range of basic beliefs about the nature of the world. Then there are those who see the scientific revolution as a product of technological change. From the printing press to the telescope, this period saw the invention of an assortment of new tools, each of which allowed for the investigation of nature and the dissemination of scientific ideas on an unprecedented scale. Finally, some historians deny that this really was a period of significant change. After all, many of the great thinkers of the scientific revolution continued to rely in some ways on much older ideas, such as those found in the Bible or in ancient Greek philosophy.⁸

Until recently, however, very few historians have stopped to consider whether they are looking in the right place to begin with. Is the history of the scientific revolution really a story about Europe alone? The answer is no. From the Aztec Empire in the Americas to the Ming Empire in China, the history of the scientific revolution is a story which incorporates the entire world. And it isn’t just that people in the Americas, Africa, and Asia happened to be developing advanced scientific cultures at the same time as those in Europe. Rather, it is the history of encounters between these different cultures which explains precisely why the scientific revolution occurred when it did.

With this in mind, I want to tell a new history of the scientific revolution. In this chapter, we explore how encounters between Europe and the Americas kickstarted a major reassessment of natural history, medicine, and geography. Much of what we know about the science produced in the New World during this period comes from the perspective of European explorers, a legacy of the history of colonization that this chapter examines. But if we look a little closer, using sources such as Aztec codices and Inca histories, we can also uncover another side to this story, one that highlights the hidden contributions of Indigenous peoples to the scientific revolution. In the next chapter, we move east, revealing how connections between Europe, Africa, and Asia shaped the development of mathematics and astronomy. Together, these chapters represent the beginning of a recurrent theme concerning the importance of global history for understanding the history of modern science. Ultimately, to account for the scientific revolution we need to look, not just to London and Paris, but to the ships and caravans which connected the early modern world.⁹

I. Natural History in the New World

After over two months at sea, Christopher Columbus finally sighted land. Sailing aboard the Santa María on behalf of the Spanish Crown, Columbus was in search of a western passage to the Indies. Instead, he encountered a whole new continent. On 12 October 1492, Columbus landed on an island he named San Salvador, part of the Bahamas. This was the beginning of a long history of European colonization in the Americas. Like many subsequent travellers to the New World, Columbus was amazed by the diversity of plant and animal life he encountered. He recorded in his diary that ‘all the trees were as different from ours as day from night, and so were the fruits, the herbage, the roots, and all things’. Columbus also quickly recognized the commercial potential of the Americas, noting that there were ‘many plants and many trees, which are worth a lot in Spain for dyes and for medicines’. Most alarmingly, the island was inhabited. On landing, the Spanish crew encountered a group of Indigenous people. Still believing he had reached the East Indies, Columbus named them indios, or ‘Indians’. Encouraged by the abundance of plant, animal, and human life, Columbus continued to explore the West Indies over the following months, reaching Cuba and Hispaniola. He later returned on three separate voyages, travelling as far as Central and South America.¹⁰

The colonization of the Americas was one of the most important events in world history. It was also an event which profoundly shaped the development of modern science, challenging longstanding assumptions about how scientific knowledge was best acquired. Prior to the sixteenth century, scientific knowledge was thought to be found almost exclusively within ancient texts. This was especially the case in Europe, although, as we’ll see in the following chapter, similar traditions existed across much of Asia and Africa. Surprising as it may sound today, the idea of making observations or performing experiments was largely unknown to medieval thinkers. Instead, students at medieval universities in Europe spent their time reading, reciting, and discussing the works of ancient Greek and Roman authors. This was a tradition known as scholasticism. Commonly read texts included Aristotle’s Physics, written in the fourth century bce, and Pliny the Elder’s Natural History, written in the first century ce. The same approach was common to medicine. Studying medicine at a medieval university in Europe involved almost no contact with actual human bodies. There were certainly no dissections or experiments on the workings of particular organs. Instead, medieval medical students read and recited the works of the ancient Greek physician Galen.¹¹

Why, then, sometime between 1500 and 1700, did European scholars turn away from ancient texts and start investigating the natural world for themselves? The answer has a lot to do with the colonization of the New World alongside the accompanying appropriation of Aztec and Inca knowledge, something that traditional histories of science fail to account for. As many early European explorers were quick to recognize, the plants, animals, and people they encountered in the Americas were not described in any of the ancient works. Aristotle had never seen a tomato, let alone an Aztec palace or an Inca temple. It was this revelation which brought about a fundamental shift in how Europeans understood science.¹²

The Italian explorer Amerigo Vespucci, after whom ‘America’ is named, was one of the first to recognize the implications of Columbus’s ‘discovery’ for natural history. After returning from his own voyage to the New World in 1499, Vespucci wrote to a friend in Florence. He reported seeing all kinds of incredible animals, including a ‘serpent’ – most likely an iguana – which the Indigenous people roasted and ate. Vespucci also recalled seeing birds ‘so numerous and of so many species and varieties of plumage that it is astounding to behold’. Most significantly, Vespucci made a direct connection between the natural history of the New World and what was known from ancient texts. He concluded with a damning criticism of Pliny’s Natural History, the traditional authority on the subject. As Vespucci noted, ‘Pliny did not touch upon a thousandth part of the species of parrots and other birds and animals’ which were found in the Americas.¹³

Vespucci’s criticism of Pliny was just the start. Over the following years, thousands of travellers returned from the New World with reports of things unknown to the ancients. One of the most influential accounts was written by a Spanish priest named José de Acosta. Born to a prosperous merchant family in 1540, Acosta was always looking to escape his comfortable but rather mundane upbringing. At the age of twelve, he ran away from home to join the Society of Jesus, a Catholic missionary organization which played a major role in the development of early modern science. The founder of the order, Ignatius of Loyola, urged his followers to ‘find God in all things’, whether that was in reading the Bible or studying the natural world. The Jesuits therefore placed great emphasis on the study of science, both as a way to appreciate God’s wisdom, but also as a means to demonstrate the power of the Christian faith to potential converts. After joining the Jesuits, Acosta attended the University of Alcalá, where he studied the classical works of Aristotle and Pliny. On graduating, Acosta was asked to go as a missionary to the New World, setting sail in 1571. He spent the next fifteen years in the Americas, travelling across the Andes in search of converts. On returning to Spain, Acosta began to write a book describing everything he had seen, from the volcanoes of Peru to the parrots of Mexico. The finished work was titled Natural and Moral History of the Indies (1590).¹⁴

Acosta witnessed many strange things in the...