The development of a critical, sceptical, speculative science that did not endorse existing beliefs but deliberately undermined them, was a historical development of exceptional importance. The foundations of a speculative intellectual life were to be found in ancient Greece, whose philosophers, poets and playwrights produced work of real originality whose central concerns, despite the passage of 2,000 years, engaged the enthusiasm of educated Europeans when the classics were rediscovered in the late medieval period. Nineteenth-century intellectuals could write as if little separated their age from that of Plato or Aristotle or Aeschylus. The critical breakthrough in understanding the nature of material reality by thinking critically about accepted world-views was begun, however, during the sixteenth and seventeenth centuries, and associated mainly with the rise of a body of experimental or deductive science based on close observation. The key names are well-known. The Polish astronomer Nicolaus Copernicus dared to argue that the earth revolved around the sun in a book only published the year of his death, in 1543; the Italian astronomer Galileo Galilei extended these observations and in many other ways paved the way for much modern physical science, utilising recent developments in the mechanical sciences; the Englishman Thomas Hobbes laid the foundations of modern political science and human psychology in his Leviathan, published in 1651; in 1687 the mathematician Isaac Newton in his Principia Mathematica announced the law of gravity and ushered in a new age of mechanical physics. The scientific and philosophical revolution precipitated by the late 17th century in Europe opened the way to developing a modern understanding of nature and natural laws and above all accepting that such things were intrinsically knowable, not part of a Divine Plan whose purpose was not to be questioned. The new principle, according to the late 18th-century Prussian philosopher, Immanuel Kant, was sapere aude—‘dare to know’.
Those who pioneered a critical, scientific view of the world ran great risks. In 1616 the Catholic Church banned Copernican teaching, and placed Galileo under house arrest for challenging scripture. Galileo was fortunate: a few years before, in 1600, Giordano Bruno, another Copernican, was burnt at the stake in Rome. Hobbes was forced into exile, suspected of atheism; John Locke, who wrote the founding text of modern liberal representative government in the 1680s was also forced to write in exile, and his works circulated in parts of Europe in secret, too subversive for open sale. Writers of the 18th-century ‘Enlightenment’, during which critical thinking began to flourish for the first time, had to steer a careful line between what could or could not be said. Rousseau was also banned for life from his native city of Geneva for his radical democratic views. But it was a tide that could not be held back. By the early 19th century most of the modern Western sciences had been established on a firm scientific basis; political and social theory exploded traditional claims to authority (expressed most clearly in the founding of the American Republic in 1776 and the French Revolution of 1789); organized religion in its Western guise was shown to be unable to defend its major contentions about the nature of the universe and of man’s place in it and an alternative, naturalistic, rational model of the world was substituted. The triumph of free expression now seems irreversible, but the revolution represented by modern thought was not inevitable and its progress was subject to fits and starts. It is still not entirely clear why the prevailing authorities in Europe came to tolerate the new intellectual wave when a century before it might have been violently suppressed. The publication in 1859 of On Liberty by the English philosopher John Stuart Mill summed up what had been achieved in modern Europe. There was no other freedom, Mill asserted, more fundamental than the right to say what you like without fear that you will be silenced.
The formal acquisition of scientific, material knowledge about all aspects of the natural world and its application to human societies has been responsible for transforming world history more fundamentally than any other development in the past 6,000 years. Whatever case can be made for showing that there are strong lines of continuity throughout world history, the possibilities opened up by transcending the narrow world view of a God-centred and God-given universe have been unprecedented. It is a story intimately bound to the wider history of the rise of Europe (which with European expansion to America came to be regarded as the Western world) over the past 500 years. Historians have often been tempted to see this is as a happily progressive narrative while the rest of the world stagnated. From a Western perspective the idea of ‘the triumph of the West’ has an evident plausibility. Yet it begs the larger question of why Europe did evolve in very different ways, not only from the other civilizations existing alongside, but from all previous civilizations. What has been distinctive about the West, as Karl Marx argued in the mid-19th century, is the fact that it proved capable of expanding world-wide; Marx thought that no other culture or civilization would be capable of withstanding what Europe had to offer or what it forced upon them.
There is no agreed or straightforward answer to the question ‘why Europe?’ Geography was clearly favourable—a temperate climate, generally adequate food supplies, population growth steady but not excessively large, few of the debilitating, parasite-borne diseases that affected large parts of Africa and Asia with elephantiasis, river-blindness, bilharzia or malaria. The long European shoreline, never very far from any human habitation, encouraged the development of seaborne trade and exploration and the development of early sea power. Seafaring technology was one of the earliest and most important of the technical revolutions and Europeans exploited it fully. Europe also succeeded in stemming the tide of regular invasion which had characterized European history for almost a thousand years from the collapse of the Western Roman Empire. The Tatar invasions of the 13th century and the expansion of the Ottoman Turkish Empire into south-eastern Europe during the early modern period were checked sufficiently to allow central and western Europe to consolidate the state system, to build a settled network of cities, and a regular trading network. The military organization of Europe was transformed by the application of gunpowder and the development of cannon and musket-fire. Although these innovations were usually used against other Europeans, they gave Europeans a clear advantage whenever they found themselves fighting non-European peoples. It is sometimes argued that post-Reformation Protestantism, with its emphasis on individualism, played an important part in making Europe different, but the earliest explorers and imperialists were Catholic Portuguese and Spanish, while the Americas were discovered by an Italian from Genoa, Cristoforo Colombo. The long history of the Crusades against the Arab Middle East showed that there was nothing passive about Catholic Christianity.
The distinctive characteristic of European societies as they solidified into an early version of the modern states’ system was their willingness to look outwards towards the wider world. The voyages of discovery were not isolated examples of a lucky piece of exploration, but rapidly embraced the whole globe, making it clear in the process that the earth was round rather than flat. Only Europeans embraced the world in this way: map-making, navigation, inland exploration, elaborate descriptions of native communities and exotic fauna and flora, all contributed to creating a view of the world fundamentally different from the view from Constantinople or Beijing. Not only did Europeans discover large areas of the hitherto unknown (at least to Europeans) but they began a process of aggressive settlement across the Americas, in parts of Africa and India and into the archipelagos of the western Pacific ‘spice islands’. If occasionally briefly reversed, European expansion proved irresistible and European appetites insatiable. The Spanish conquistador Hernán Cortés captured the Aztec capital Tenochtitlán in 1520 with 300 Spanish troops and some local allies aided by the fact that around half the city’s 300,000 inhabitants had died of imported smallpox. Once the imperial toeholds were established across the oceans, Europeans never abandoned them. They became a source of remarkable wealth, helping eventually to make Europe richer than any rival civilization, and making it possible