Where did the ideas come from that became the cornerstone of American democracy? Not only the erudite Thomas Jefferson, the wily and elusive Ben Franklin, and the underappreciated Thomas Paine, but also Ethan Allen, the hero of the Green Mountain Boys, and Thomas Young, the forgotten Founder who kicked off the Boston Tea Party. These radicals who founded America set their sights on a revolution of the mind. Derided as "infidels" and "atheists" in their own time, they wanted to liberate us not just from one king but from the tyranny of supernatural religion.

The ideas that inspired them were neither British nor Christian but largely ancient, pagan, and continental: the fecund universe of the Roman poet and philosopher Lucretius, and the potent (but nontranscendent) natural divinity of the Dutch heretic Benedict de Spinoza.

Drawing deeply on his study of European philosophy, Matthew Stewart pursues a genealogy of the philosophical ideas from which America's revolutionaries drew their inspiration, all scrupulously researched and documented and enlivened with storytelling of the highest order. Along the way, he uncovers the true meanings of "Nature's God", "self-evident", and many other phrases crucial to our understanding of the American experiment but now widely misunderstood. Stewart's lucid and passionate investigation surprises, challenges, enlightens, and entertains at every turn, as it spins a true tale and a persuasive, exhilarating argument about the founding principles of American government and the sources of our success in science, medicine, and the arts.