Ideas: A History from Fire to Freud

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 and 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 between natural law and human law.²⁵