1. Leaves of Grass Philosophy begins in wonder," Socrates said. It matures, Hegel added, in terror, on the "slaughter bench" of history. So it was with the arrival of the Spanish in the New World. Wonder there was when Christendom realized there existed another half a world, filled with rarezas , rarities, curious plants and animals but above all people, many more and many more different kinds than lived in all of Europe. Even before Copernicus, Europe was awakening to the idea that the Earth wasn''t the center of existence, and that the universe contained, Giordano Bruno would soon reckon, "innumerable suns" and "infinite earths that equally revolve around these suns." Scholars intuited a link between the celestial and earthly multitudes. There was one heavenly realm, containing an incalculable number of stars.

There was one earthly estate, now known to contain many more millions of people than previously imagined. The realization that the earth was not the center of divine creation was as unsettling as the knowledge that Europe wasn''t the center of the world. What did this multiplication mean for the idea of Catholic holism, for the story of Genesis when God at Creation called into being first Adam, then Eve, who together produced a single linaje , or lineage, of descendants with a shared, if gory, history? When reconciled with the Catholic premise of celestial unity, the diversity of the New World''s peoples could support the ideal of equality. Time spent in the Caribbean, Mexico, and Central America convinced the Dominican priest, Bartolomé de las Casas, that the ancient philosophers and theologians who had argued that there existed categories of inferior humans, people born to be "natural slaves," were wrong. As it turned out, Las Casas wrote, the ancients didn''t "know very much" about the world. The Dominican would continue to cite the sages when it suited his purpose, but for him, now, truth was to be found not in Aristotle but in America-and the most important truth was that humans everywhere were fundamentally the same. All were made in God''s image. Their differences-skin color, hair texture, cultural practices, and religious beliefs-reflected the vast variety of the infinite divine.

And differences in appearance had nothing to do with human essence, which for Las Casas was everywhere the same. Every Indian he had met in the New World, he said, possessed both free will and the ability to reason. That alone made them human. They could remember the past, imagine the future, estimate probabilities, and could see, hear, feel, smell, and taste. They were born, matured, grew old, and became ill, and when they died their families grieved, as humans did everywhere. When happy, they laughed. When sad, they cried. They took delight in the good and despised the bad.

From this, Las Casas issued a famous declaration: Todo linaje de los hombres es uno -All humanity is one. At the same time, the New World''s conquerors mocked the idea of humanity''s oneness, laying the foundation for race supremacy. Spanish settlers and colonists legitimated cruel killing on an unprecedented scale, forcing the New World''s inhabitants to labor in mines, fields, and waters, to extract the riches of America-gold, silver, pearls, dyes, and soon sugar and tobacco-that Europe would use to gild its empires, muster its armies, fund its wars, build its cathedrals, and pay for more voyages of conquest and enslavement. Never mind what priests like Las Casas were saying. Theologians were known to say one thing and its opposite. Indians were little better than apes put on earth to serve man. To dominate them was just. To work them to death no more a sin than to butcher a hog.

An Infinity of People The people of the New World were "found." Then they were lost. Not immediately and not completely, but enough so that a group of Dominican and Franciscan priests wrote their superiors in Spain in 1517 wanting to know where they went. "Where are they, oh most illustrious fathers?" What happened to the men and women who upon Columbus''s arrival two decades earlier were so many that they were like "leaves of grass?" Demographers today aren''t sure what the size of America''s population was before the arrival of the Spanish. Most estimates fall between fifty and one hundred million inhabitants. The Spanish couldn''t say. They knew that the Indies (the name América was in use for the New World in the early 1500s but not widely adopted until a little later) were densely populated with wildly varied peoples. They ranged from the elysian Taino, who seemed to have lived lush and well-nourished lives on the islands of the Caribbean; to the hierarchically organized, ostentatious, and scientific Aztec and Inka Empires in Mexico and Peru.

Columbus thought the island of Hispaniola-Spain''s first Caribbean colony, from where Hernando Cortés would soon lead his assault on Mexico-was "paradise," but a populated paradise, completely "cultivated like the countryside around Cordoba." He estimated that the island was home to over a million souls. Las Casas, who, seventeen years old, arrived in the Caribbean on April 15, 1502, thought that number too low. "An infinity of people" lived in the new lands, he later wrote. The New World was "filled with people, like a hive of bees." "It was," he said, "as if God had placed all, or the majority, of the entire human race in these countries." Later, European romantics would use the word sublime to describe the sensation evoked by confrontation with the grandeur and terror of nature, its existential enormity. And there''s some of this feeling in the letters and chronicles left by Spanish warriors.

As the Conquest proceeded, as Cortés began his march through Mexico, they wrote of their exploits climbing high peaks equal to the Alps, navigating great river systems, and trekking through dense forests. The volcano Popocatépetl rained fire and ice, bursting, Cortés wrote King Charles, with "so much force and noise it seemed as if the whole Sierra was crumbling to the ground." Yet it wasn''t nature that bedazzled the Spaniards as much as the "great city" of Tenochtitlán sitting below the volcano. "As large as Seville," Cortés wrote, and more populated than London, with "many wide and handsome streets," fine noble houses, engineered canals, and a complex hydroponic agricultural system. Further south, it wasn''t volcanic eruptions that shivered European souls. It was Mapuche warriors overspread across a vast Andean valley mustered to defend their land. They "shook the world around them," one conquistador wrote, "with sudden dread." There were so many people.

Then they began to die. The consensus is that the population was cut by between 85 to 95 percent within a century and a half. The Spanish Conquest, driven forward at a relentless pace by the consolidating Kingdom of Castile, inaugurated what the demographers Alexander Koch, Chris Brierley, Mark Maslin, and Simon Lewis call history''s "largest human mortality event in proportion to the global population," a drop of upward of 56 million people by 1600. "The greatest genocide in human history," wrote Tzvetan Todorov in the 1980s. The first wave of death was brought by Conquistador terror. All the World Knows Bartolomé de las Casas''s transformation into a critic of the Conquest didn''t happen until after the Conquest had made him rich. As a young boy growing up in Seville-he was born in 1484-Bartolomé had witnessed the glory heaped on Columbus upon his return from his first cross-Atlantic voyage and heard the stories of islands filled with gold, spices, and potential slaves. His merchant father, Pedro, and uncles Francisco and Juan were part of Columbus''s crew, and Pedro used the wealth he acquired from sailing to pay for his son''s education.

Bartolomé became a "good Latinist" and began studying to become a priest. When Las Casas first landed in Hispaniola (today divided by Haiti in the west and the Dominican Republic in the east), his head was already crowned with a friar''s tonsure. He worked with his father, who had given up sailing to settle on the island as a merchant. Las Casas continued his religious studies and, in 1507, traveled to Rome for his ordination. He was gone for two years, returning to the Caribbean in 1509, and in his later writings was circumspect about his own service to the Conquest. He accompanied at least one incursion into Hispaniola''s western lands, provisioning troops with supplies but also perhaps lending a hand to put down Indians with sword and harquebus. Christopher Columbus''s son, Diego Colón, Hispaniola''s governor, granted him an encomienda , or consignment of Indian laborers, on the north coast of the island in the Cibao Valley. The term encomienda refers to a kind of slavery, but indios encomendados , or commended Indians, weren''t considered private property, or chattel.

Rather, they were formally something like wards, members of an existing village or community, who, in exchange for labor, were to receive instruction in Christian doctrine from their overlords, their guardian encomenderos. The encomienda was important, but it was just one of many coerced labor systems. There was out-and-out enslavement, of Native Americans and Africans; there were onerous tribute demands and a labor corvée called the repartimiento . The "Conquest brought about so many forms of Indian servitude," wrote one historian in the early 1900s, "that it is very difficult to master the nature of them all, and to follow them into all their minute details." Las Casas''s conversion.