In Section 4, Standage turns his attention from alcoholic drinks to caffeinated ones, beginning with the role of coffee during Europe's Age of Enlightenment. By the early seventeenth century, European thinkers were beginning to challenge the principles laid down by Ancient Greek philosophers. This was made possible, in part, by the religious wars of the Protestant Reformation, which questioned the once infallible authority of the Catholic Church and opened the way for a scientific revolution. The popularity of this new, rational approach coincided with the increasing popularity of coffee.

Importantly, coffee provided an alternative to alcohol that was safe to drink and which made people more alert. During the seventeenth century, most drinks were alcoholic to some degree, whether it was weak beer or watered down wine, and coffee became the antithesis of these drinks. Like many innovations, coffee originated in the Arab world; it “seems to have first become popular in Yemen in the mid-fifteenth century” (137) where it was used in Sufi rituals. While it was non-alcoholic, and therefore permitted by Islam, coffee was not without controversy. Some Muslim scholars argued that coffee was, in fact, intoxicating, while for others, the coffeehouse represented the dangerous possibility of political dissent.