equality within one and the same nation, and the perfecting of mankind. William Godwin (1756-1836), the English anarchist, thought that the three chief ideas that would produce the all-important goal in life- the triumph of reason and truth-were literature, education and (political) justice. Thomas Carlyle (1795- 1881) noted 'the three greatest elements of modern civilisation [are] gunpowder, printing and the Protestant religion', while Auguste Comte (1798-1857) idealised three stages of history-theological, metaphysical and scientific, later expanded to theological-military, metaphysical-legalistic, and scientific-industrial.15 Later still in the nineteenth century the anthropologist Sir James Frazer distinguished the ages of magic, religion and science, while Lewis Morgan, in his Ancient Society , divided history into the stages of savagery, barbarism and civilisation, and thought that the main organising ideas of civilisation were the growth of government, the growth of ideas about the family, and the growth of ideas about property. Not everyone has fallen into this tripartite way of looking at history. Condorcet thought there had been ten stages of progress, Johann Gottfried Herder divided history into five periods, Georg Wilhelm Hegel divided it into four, and Immanuel Kant believed that progress had gone through nine stages. Nevertheless, W. A. Dunlap, writing in 1905, used the word 'triposis' to describe this tendency to divide intellectual history into three, while Ernest Gellner in 1988 favoured the term 'trinitarian'.16 In recent years we have had J. H. Denison's Emotions as the Basis of Civilisation (1932), which divided societies into the patriarchal, the fratriarchal and the democratic. In 1937, in his Intellectual and Cultural History of the Western World , Harry Elmer Barnes described three great changes in 'sensibility' in history-the arrival of 'ethical monotheism' in the Axial Age (700-400 BC), the advent of individualism in the Renaissance, when the present world became an end in itself instead of a preparation for the shadowy afterlife, and the Darwinian revolution of the nineteenth century.17 Economists have often thought in threes. In The Wealth of Nations (1776), Adam Smith (1723-1790) offered a pioneering analysis of the fundamental division of income into rents, wages and the profits of stock, identifying their respective owners as the landlord, the wage-earner and the capitalist, the 'three great, original and constituent orders of every civilised society'.18 Even Marxism can be reduced to three: an age when man knows neither surplus nor exploitation, when both surplus and exploitation are pervasive, and when surplus remains but exploitation is ended.19 And Karl Polanyi, in The Great Transformation (1944), distinguished three great economic epochs-reciprocity, redistribution and the market. Two years later, in The Idea of History , R. G. Collingwood described 'three great crises' that have occurred in the history of European historiography. The first occurred in the fifth century BC, when the idea of history as a science came into being; the second took place in the fourth and fifth centuries AD, with the advent of Christianity, which viewed history as the working out of God's purpose, not man's; and the third came in the eighteenth century with a general denial of innate ideas and intuitionism or revelation. In 1951, in Ideas and Men , Crane Brinton, professor of ancient and modern history at Harvard, identified humanism, Protestantism and rationalism as the three great ideas making the modern world. Carlo Cipolla published Guns and Sails in the Early Phase of European Expansion, 1400-1700 in 1965, in which he argued that nationalism, guns and navigation accounted for the European conquests which created the modern world. The rising nationalism in Europe, as a result of the Reformation, led to a new round of war, which promoted the growth of metallurgy, and ever more efficient-and brutal-weapons. These far outstripped anything available in the East (in contrast to the situation in 1453, when the Turks sacked Constantinople), while the developments in navigation, fuelled by ambitions of empire, enabled European ships to reach both the far east (the 'Vasco da Gama' era) and, eventually, the Americas.20 In Ernest Gellner's Plough, Sword and Book (1988), he argued that there have been three great phases in history-hunting/gathering, agrarian production and industrial production-and that these fitted with the three great classes of human activity-production, coercion and cognition. In 1991, Richard Tarnas, in The Passion of the Western Mind , argued that philosophy, in the West at any rate, can be divided into three great epochs-as largely autonomous during the classical period, as subordinate to religion during the dominant years of Christianity, and as subordinate to science ever since.21 In his book Fire and Civilisation (1992), Johan Goudsblom argued that man's control of fire produced the
first transformation in human life. Early man was now no longer a predator: control of fire enabled him to corral animals and to clear land. Without this, agriculture-the second transformation-would not have been possible. Control over fire also introduced the possibility of cooking, which distinguished man from the animals and may be regarded as the origins of science. (The use of smoke may also have been the first form of communication.) Control over fire, of course, also led to baking, ceramics and smelting (the 'pyrotechnic cultures'), which enabled metal daggers and then swords to be constructed. But the third great transformation, and the most important, after agriculture, Goudsblom said, was industrialisation, the union of fire with water, to produce in the first instance steam, harnessing a new form of energy which enabled machines of unprecedented size and power to perform certain routine skills much better and much faster than was possible by hand.22 Isaiah Berlin, the Oxford political philosopher, thought there had been three great political/psychological turning-points in history. The first came after the death of Aristotle, when the philosophical schools of Athens 'ceased to conceive of individuals as intelligible only in the context of social life, ceased to discuss the questions connected with public and political life that had preoccupied the Academy and the Lyceum, as if these questions were no longer central...and suddenly spoke of men purely in terms of inner experience and individual salvation'.23 A second turning-point was inaugurated by Machiavelli, which involved the recognition that there is a division 'between the natural and the moral virtues, the assumption that political values are not merely different from, but may in principle be incompatible with, Christian ethics.' The third turning-point-which Berlin says is the greatest yet-was the advent of romanticism. These changes are discussed in Chapter 30. Finally, in 1997, in Guns, Germs and Steel , Jared Diamond picked up where Cipolla left off: his concern was to explain the way the world developed before modern times and why Europe discovered (and conquered) America rather than vice versa. His answer had three broad themes. Eurasia, he pointed out, is mainly an east-west landmass, whereas the Americas are north-south. The exigencies of geography, he said, mean that the migration of domesticated animals and plants is by definition easier along latitudes than it is along longitudes, which meant that cultural evolution was likewise easier, and therefore faster, in Eurasia than it was in the Americas. Second, Eurasia had more mammals capable of domestication than in the Americas (fifteen, as opposed to two), and this also helped civilisations evolve. In particular, the domestication of the horse, in Eurasia, transformed warfare, which encouraged the development of the sword, which helped the evolution of metallurgy, meaning that European weapons far outstripped their equivalents in the New World. Third, domestication of many animals meant that European humans evolved immunity to the diseases which those animals carried and which, when they were introduced into the New World, devastated the population.24 It is encouraging that there is a measure of overlap here. Agriculture, weapons, science, industrialisation, and printing, for example, are each selected by more than one author. These arguments and ideas certainly help us begin to find our way about a massive field but, as will become clear later in this Introduction, and then throughout the book, though I think that all these ideas and innovations are important, my own candidates are very different. Of course, this is by no means the only way of looking at the development of ideas-by identifying the most influential innovations and abstractions of all time. In their book, The Western Intellectual Tradition , Jacob Bronowski and Bruce Mazlish identify three 'realms' of intellectual activity, an approach that I have found very useful. There is first the realm of truth: the effort to inquire into truth is the concern of religion, science, philosophy where, in an ideal world, agreement would be total and involuntary-i.e., inevitable in a logical, mathematical or syllogistical sense. Next, there is the search for what is right: this is the concern of law, ethics and politics, where agreement, largely voluntary, need not be total but in order to work still needs to be widespread. And thirdly there is the realm of taste, which is largely the business of the arts, where agreement is not necessary at all and where disagreement may be fruitful. Of course, there is again a measure of overlap between these realms (artists search for the truth, or say that they do, religion is concerned with what is right as well as with what is true) but the distinction is worth bearing in mind throughout this book. The Greeks early on recognised an important distinction