The greatest non-fiction works in English?

Ben Stein in the conservative US magazine The American Enterprise, November 1999:

In 1776, without the benefit of word processing, the Internet, or Starbucks Coffee, three of the four greatest non-fiction works in the English language were published. In America, Thomas Jefferson, with some help, wrote the [American] Declaration of Independence. In Great Britain, Gibbon produced his masterpiece, The Decline and Fall of the Roman Empire. And in Scotland, Adam Smith wrote The Wealth of Nations, by far the most important work of political economy ever published. (The fourth and perhaps most important document of all, the U.S. Constitution, came about a decade later.)