I'd go even farther than Eisenstein. Printing soon brought literacy to vast numbers of people (eventually to the vast majority of us). Printing, especially printing in newly standardized vernaculars, changed the very consciousness of people, and turned a small corner of the world, Western Europe, into a culture that in many ways conquered the world. Widespread decentralized printing and the accompanying book markets, new schools, and rise of literacy gave rise to a new form of consciousness -- book consciousness.
Colombus was among the first generation of navigators who had been reading avidly and widely since a child. On his bookshelf was Marco Polo's Travels. On his voyages he carried maps made by geographers who had been literate sincethey were children, and he carried astronomical tables that had been printed widely across Europe. These tables had been made by a Hungarian-Italian mathematician whose bookshelf was full of ancient Greek science and mathematics. Such information had been rather inferior and far less available just a few decades before.
With the easy conquest by tiny Portugal of Asia's vast and ancient sea trade routes, rapidly literizing Western Europeans were by the early 16th century demonstrating a vast superiority in naval affairs. In navigation as in battle officers using accurate charts and astronomical tables were at a premium. (Europeans did not have quite such good luck on land against the Turks). Western Europeans would retain completely uncontested (except among each other) naval superiority on the world's oceans until the Japanese victory over Russia in the early 20th century. The Japanse by then had long since taken up printing and had a very well read population . Even on the ground by the 18th century English merchants, officers, and civil servants, practically all of them literate and widely read since young children, were finding it quite easy to conquer and take over the administration in far larger and otherwise highly advanced civilizations like India.
Soon after the spread of the printing press, the very fundamentals of organization in Western Europe began to change. In the late Middle Ages organizations, even royal and papal bureaucracies and banking "super-companies", rarely engaged more than a few dozen employees. Organizational size came up against the severe limit of the Dunbar number. By the end ofthe 16th century, the colonial companies and bureaucracies of Spain and Portugal were vast, highly literate, and well coordinated. Officer corps had often been raised on military books and thus able to draw lessons from a wide variety of ancient and recent battles. Even a minor salt extractor in Wear, England, was employing 300 men by the mid 16th century. (Large organizations in manufacturing would largely have to wait until the 18th century and the industrial revolution, however).
Before book consciousness there had been no national languages, but only a range of often mutually incomprehensible dialects and in Western Europe the language of the tiny literate elite, Latin. With newly unified national vernaculars, organizations were able to coordinate and grow in an unprecedented manner. A much larger group of people, raised on the same written language, increasingly also came to look and speak similarlyand become far more mutually trusted. It was the birth of national loyalty and nationwide webs of trust. The "tribe" to which we are instinctively loyal vastly increased in size. The pool of already somewhat trusted "same tribe" people from which a bureacracy could recruit new members vastly increased. National polities and militaries were able to coordinate political, economic, and battlefield strategies in an unprecedentedmanner. The 16th century saw the first major growth of the joint-stock corporation, enabling far more capital to be invested in the enlarging organizations that engaged in mining and manufacture as well as government and conquest. This development is probably a response to the new ability to form larger organizations, since the basic ideas (corporate law, shares of stock, etc.) had already been in use in Europe for quite some time. Some of the early English 16th century joint-stock companies included military expeditions (Drake's privateering voyages and naval actions were financed through joint stock companies: a different company for each expedition), trading and slaving companies (the Muscovy and Guniea companies) and mining and manufacturing companies (the Royal Mining Company and the Royal Batteries & Mines Company). The most famous became the English East India Company, but many of the American colonies were also joint-stock corporations. The first widely traded and initially most successful joint-stock company was the Dutch East India company,which quickly grew far beyond the Dunbar number to have thousands of employees.
Book consciousness changed almost every profession. Good books on a trade could greatly increase the knowledge imparted during apprenticeships, and indeed eventually led to the end of the apprecenticeship system. Meanwhile, widely printed books on mathematics and science, such as Euclid's Geometry, gave knowledge that could be used in a wide variety of occupations, and training was often restructured to assume and build upon such new general knowledge. This led to a profound change in labor productivity, moving mankind away from the Malthusian curve and (along with the expansion of organizational size beyond the Dunbar limit) eventually to the industrial revolution.
A typical example of the rise of book consciousness was the radical improvement in how cases were reported in the English legal system by the late 16th century. For the first time, cases and statutes were widely and accurately cited. This reflected the fact that judges, barristers, attorneys, and even some of the parties had for the first time printed books of statutes and cases at their fingertips -- instead of having to find the single copy of a scroll hidden away in some monk's or bureacrat's library. The first great English opinion writer, Sir Edward Coke, dates from this period. In turn, the wide availability of printed statute and case law led to basic changes in the way we interpret and view the law.
Almost invariably, during the colonial period, when largely illiterate cultures (i.e. cultures where mostof the second-tier nobility, military officers, and merchants, and almostall craftsmen and farmers, had not been raised on books) were encountered by literate Europeans, the latter described the former with severe ephithats, suchas "savages." This makes our forbears seem odious to us, who understand that all human races are capable of literacy, and indeed by now book consciousness has spread to most of the globe and most of us encounter a widevariety of highly literate people every day. However, at least in the 16th century for book-raised Western Europeans this was not so much a racialprejudice as a largely accurate observation. "Savage" was applied not only to neolithic Africans and Americans, but also to Irish backlanders and Scottish highlanders. There was a similar Western European attitude to otherwise very advanced civilizations in India and China. From the 16th century onward, any culture that did not have book consciousness was a culture of savages.
It's possible that today the availability of thousands of times still more material to read, readily accessible by search engine, and the expansion of a small number language groups (but especially English) to a worldwide real-time network is creating a new "Internet consciousness." People within this network may soon come to see people outside of it as savages. But that is a topic for another post.