The Enlightenment Is Hard to Define

Left to right: Adam Smith, James Madison (above Smith), Denis Diderot, David Hume, Thomas Jefferson, Immanuel Kant, Thomas Paine (above Kant), and John Locke. See AARevolution.net for more images of the American Revolution.

Updated: April 7, 2026 Intellectual Foundations of the American Revolution — Part I The Enlightenment is not as easy to define as we might expect—largely because the term itself was rarely used by the very thinkers we now group under it. In many ways, “the Enlightenment” is a label applied after the fact, used to […]